Need help re-wiring thermosensor..
03-09-05, 04:19 PM
#26
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Haven't had to produce rebuttals with you for a while now, NZ, lol...
You'll notice I chose my words carefully- I stated that it ACTS as a reverse thermocouple, not that it was. I did this to try to clarify things a bit for the guys.
You are correct, it's basically a negative temp coefficient thermister, but who the heck knows what that is if I would have said that?
So you're saying that on the turbos, the common ground loop for those sensors actually grounds BEFORE the circuit makes its way back to the ECU? That is strange, if so...
You'll notice I chose my words carefully- I stated that it ACTS as a reverse thermocouple, not that it was. I did this to try to clarify things a bit for the guys.
You are correct, it's basically a negative temp coefficient thermister, but who the heck knows what that is if I would have said that?
So you're saying that on the turbos, the common ground loop for those sensors actually grounds BEFORE the circuit makes its way back to the ECU? That is strange, if so...
03-09-05, 11:12 PM
#27
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Originally Posted by WAYNE88N/A
You'll notice I chose my words carefully- I stated that it ACTS as a reverse thermocouple, not that it was.
So can you explain to me how this circuit actually works? I've never been completely sure. I presume the ECU measures the varying current through the circuit or something?
03-10-05, 01:13 AM
#28
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The water thermosensor is NOT a resistor, and it does NOT receive 5v from the ECU. It acts as a reverse thermocouple, that is, it produces its own electrical current inversely proportional to the amount of heat it receives (much like our O2 sensors, but backwards). Accordingly, this voltage is tiny (.4 to 1.8 volts is spec, the hotter the coolant, the lower the voltage**********
I beg to differ. Ain't so.
I beg to differ. Ain't so.
03-10-05, 08:39 PM
#30
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Originally Posted by HAILERS
I beg to differ. Ain't so.
All right, this is my best guess, based on assumptions, for you, Hailers. Note that this based on my cars' schematic- the turbos may be different.
We know that we read that .4 to 1.8v at the ECU, and that this is the only wire (other than the ground side) that electrically connects the sensor to the ECU. If this was a 5 volt sensor, we'd see 5v there at the ECU pin, because we're on the power side of the component. Since we don't, the power (voltage) has to be coming from the sensor side of the circuit, not the ECU side (let's say the ECU was powering the circuit- if so, then reading voltage at that pin would produce the same voltage no matter what the resistance of the sensor is, because the voltage drop wouldn't occur until AFTER the sensor, on the ground side).
Remember, the Japs wired this car backwards- not really, but that's what it seems like following the FSM troubleshooting steps- when we see 12v at certain ECU pins, it means that the circuit is OFF, and 0v means it's on. Hard to wrap your head around, eh?
Now, back to the sensor. If we subscribe to the theory that the ground side of any circuit actually supplies the current (myself and Aaron are the only ones that I know of that view circuits this "quantum theory" way), our power supply for the sensor is magically found. Remeber, it shares the ground with all of the other 5v sensors, so electrically, it's on the same electrical potential "plane" that they are. This is good, because the ECU can then accurately map each input against each other to produce the best fuel scheduling output.
So, it's a temperature-sensitive thermister, with a positive coefficient: temp goes up, resistance goes up, voltage goes down...
I know, I said it had a negative coefficient earlier...It does, if you're comparing voltage & temps...
Any brilliant insights to add to my faltering guesswork?
03-10-05, 10:30 PM
#31
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You seem convinced. I have doubts......so I'll go out to the car and take a look. Personally I see over two volts easily when the weather is cold and I seriously doubt it's coming from the sensor to the ECU. But I'll try to have an open mind about it.
03-10-05, 10:49 PM
#32
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Yes, that .4 to 1.8v is with the car idling, IIRC.
Come to think of it, I had more than 1.8v I recorded back when I was playing with all of my sensors...
Irregardless, there is no 5v common wire going to that sensor (on my car, anyway)...
The voltage we read at that ECU pin has to be coming FROM the sensor if it varies at that ECU pin- think about it...
Come to think of it, I had more than 1.8v I recorded back when I was playing with all of my sensors...
Irregardless, there is no 5v common wire going to that sensor (on my car, anyway)...
The voltage we read at that ECU pin has to be coming FROM the sensor if it varies at that ECU pin- think about it...
03-11-05, 01:55 AM
#33
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I think you guys are crazy ;D lol
But I am following best I can, thanks for figuring this out! =D
The most I know is that in electronics class they told us that you only think of the power flowing from positive to negative for THEORY but in reality it doesn't actually happen that way, it's the other way around... we just use the old way 'cause it's always been taught that way or something.
Anyway, cool stuff. =)
--Gary
But I am following best I can, thanks for figuring this out! =D
The most I know is that in electronics class they told us that you only think of the power flowing from positive to negative for THEORY but in reality it doesn't actually happen that way, it's the other way around... we just use the old way 'cause it's always been taught that way or something.
Anyway, cool stuff. =)
--Gary
03-11-05, 12:54 PM
#34
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Originally Posted by WAYNE88N/A
Yes, that .4 to 1.8v is with the car idling, IIRC.
Come to think of it, I had more than 1.8v I recorded back when I was playing with all of my sensors...
Irregardless, there is no 5v common wire going to that sensor (on my car, anyway)...
The voltage we read at that ECU pin has to be coming FROM the sensor if it varies at that ECU pin- think about it...
Come to think of it, I had more than 1.8v I recorded back when I was playing with all of my sensors...
Irregardless, there is no 5v common wire going to that sensor (on my car, anyway)...
The voltage we read at that ECU pin has to be coming FROM the sensor if it varies at that ECU pin- think about it...
03-13-05, 08:00 PM
#35
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Beating a dead horse here, but what the hell...
I've never tried reading at the plug, Hailers. Didn't see a point in it (until now, maybe, lol). Everything I've stated I've gleaned from the FSM schematic. Maybe the schematic's SNAFU'd, I don't know. Wouldn't be the first time I've found discrepancies in our FSMs, for sure.
Here's what I see (follow along on page 50-31 of the S4 FSM, if you wish): There is one wire connecting the ECU and the water thermo sensor. It is a SIGNAL wire, denoted by the directional arrow Mazda so gratuitously provided for us. If there was 5v with the plug disconnected, then there should also be 5v at the ECU pin with the plug connected, because there is nothing to drop the voltage between the ECU and the sensor plug. And, as we well know, we don't get 5v at that ECU pin with the key on. More like 2v, with a cold engine...
Again on the schematic, the 5v ref wiring does not run to that sensor. Why?...I don't know, but I do know that the actual 5v ref pin (2A) shows the arrow as a "supply" wire for the other sensors, as it should (versus the green/white from the thermo, which shows a signal run TO the ECU...
While perusing this same schematic, you'll also note that the intake air temp sensor on the dynamic chamber operates electrically exactly as the water thermo sensor, that is, one signal wire running to the ECU, and the ground wire...
I'm beginning to think that this common "ground" run between these sensors isn't actually a ground after all. For one, why run a seperate ground wire to components that actually mount to a grounded engine block, and for another, this gang circuit originates in the AFM, seperated by nothing more than a potentiometer coil from that 5v input ref wire. In other words, the sensor "grounds" are not even grounds at all, but a low voltage power supply for the water thermo sensor and others. Fairly neatly explains how that sensor gets it's power, doesn't it?
NOW you're running to look at the schematics, aren't you???
Here's my smiley face
I've never tried reading at the plug, Hailers. Didn't see a point in it (until now, maybe, lol). Everything I've stated I've gleaned from the FSM schematic. Maybe the schematic's SNAFU'd, I don't know. Wouldn't be the first time I've found discrepancies in our FSMs, for sure.
Here's what I see (follow along on page 50-31 of the S4 FSM, if you wish): There is one wire connecting the ECU and the water thermo sensor. It is a SIGNAL wire, denoted by the directional arrow Mazda so gratuitously provided for us. If there was 5v with the plug disconnected, then there should also be 5v at the ECU pin with the plug connected, because there is nothing to drop the voltage between the ECU and the sensor plug. And, as we well know, we don't get 5v at that ECU pin with the key on. More like 2v, with a cold engine...
Again on the schematic, the 5v ref wiring does not run to that sensor. Why?...I don't know, but I do know that the actual 5v ref pin (2A) shows the arrow as a "supply" wire for the other sensors, as it should (versus the green/white from the thermo, which shows a signal run TO the ECU...
While perusing this same schematic, you'll also note that the intake air temp sensor on the dynamic chamber operates electrically exactly as the water thermo sensor, that is, one signal wire running to the ECU, and the ground wire...
I'm beginning to think that this common "ground" run between these sensors isn't actually a ground after all. For one, why run a seperate ground wire to components that actually mount to a grounded engine block, and for another, this gang circuit originates in the AFM, seperated by nothing more than a potentiometer coil from that 5v input ref wire. In other words, the sensor "grounds" are not even grounds at all, but a low voltage power supply for the water thermo sensor and others. Fairly neatly explains how that sensor gets it's power, doesn't it?
NOW you're running to look at the schematics, aren't you???
Here's my smiley face
03-15-05, 03:48 PM
#36
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************NOW you're running to look at the schematics, aren't you???***************
Naw. I went out to the car the other day, and seeing as how it's difficult to reach the water thermo sensor plug, I went to the ECU and pulled the green white wire out and installed a segment of wire/pin from an old ECU plug,....turned the key to ON and read the five volts on that little piece of wire that was connected to nothing else. Five volts.
Soooo, your suggesting I go ou to the car and ground the brown/black wire of the water thermo sensor to a ground. And then look at the green/white wires output. Right? Right. Well, someday, but not today. Especially since the FSM says that 2C is a ground and we know the fsm is NEVER wrong. Well maybe on the checkout of the tps's A to C resistance at full throttle, but hey, no one is perfect. Man, have you ever looked at the MSD for Skykol???? Uggggh!
Naw. I went out to the car the other day, and seeing as how it's difficult to reach the water thermo sensor plug, I went to the ECU and pulled the green white wire out and installed a segment of wire/pin from an old ECU plug,....turned the key to ON and read the five volts on that little piece of wire that was connected to nothing else. Five volts.
Soooo, your suggesting I go ou to the car and ground the brown/black wire of the water thermo sensor to a ground. And then look at the green/white wires output. Right? Right. Well, someday, but not today. Especially since the FSM says that 2C is a ground and we know the fsm is NEVER wrong. Well maybe on the checkout of the tps's A to C resistance at full throttle, but hey, no one is perfect. Man, have you ever looked at the MSD for Skykol???? Uggggh!
03-15-05, 04:38 PM
#37
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Okie Dokey, at this point I can't argue that you're getting 5v on that wire. I'm too lazy to go check my car. It had me baffled, since I knew that it wasn't coming from the ECU. It's gotta be coming from that "ground" circuit (that starts at that AFM pot). The funny thing is, the thermo sensor is a variable resistor (according to the symbol on the schematic, anyways), so if it's got +5v on the "ground" side, it should have somewhat less than 5v on the ECU side.
The even funnier thing is, that "ground" circuit actually reads to ground at 2c at the ECU, and we all know that a grounded circuit can't have positive voltage on it. The ECU must have some form of an internal shunt or cap circuit to prevent a direct short...
I think at this point we can safely say that it's not a ground circuit after all (even though we've been saying that for years), but a completely isolated power supply circuit for the low-voltage sensors. Maybe it's used as a "comparator" circuit for the actual ECU 5vref circuit, I don't know at this point...
OR the schematic is missing something, lol...
You do see the connection at the AFM I'm talking about, right?
PS- yep, Skydrol is some nasty stuff, I've had it sprayed in my eyes more than once...Ultimate pain
The even funnier thing is, that "ground" circuit actually reads to ground at 2c at the ECU, and we all know that a grounded circuit can't have positive voltage on it. The ECU must have some form of an internal shunt or cap circuit to prevent a direct short...
I think at this point we can safely say that it's not a ground circuit after all (even though we've been saying that for years), but a completely isolated power supply circuit for the low-voltage sensors. Maybe it's used as a "comparator" circuit for the actual ECU 5vref circuit, I don't know at this point...
OR the schematic is missing something, lol...
You do see the connection at the AFM I'm talking about, right?
PS- yep, Skydrol is some nasty stuff, I've had it sprayed in my eyes more than once...Ultimate pain
03-15-05, 04:56 PM
#38
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I've done a number of things to my 87 car and one of those THINGS is that I have pin 2C spliced to a homemade ground. At least the last time I looked it was. And I guarantee my boost/pressure sensor works like a champ along with my TPS, AFM, WATER TEMP SENSOR, VARIABLE RESISTOR, ATMOSPHERIC PRESSURE SENSOR and the thing or two I don't have a memory for. It's a ground wire, that pin 2C. At least it is on my car. I THINK even the SAFC is connected to that wire from 2C (memory, shooting from the hip).
03-15-05, 07:13 PM
#39
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All right, let me get this straight- on your S4, at ECU pin 2I, you get 5v dc with the key on? Doesn't matter if the wire is connected at that pin or not, you still get 5v, right? To ground, I presume?
That makes no sense, for a couple of reasons; one being that if the ECU is supplying 5v on that wire, there is no wire to return the signal back to the ECU after the voltage has been dropped by the thermo sensor. Another reason is that the FSM calls for .4 to 1.8v at idle (key on, obviously). Why read 5v with just the key on, yet read (say) 1.5v with the car idling, right after start? The sensor is still the same temp right after start, how does the voltage drop so much?
BTW, I see that I've recorded a 2.2v at that pin with key on, cold engine, at 75*F...
Another reason is that the FSM shows that green/white wire as being a signal return to the ECU from the thermo sensor, not a voltage supply (as is the brown/white 5vref wire at pin 2A).
Could you have perhaps screwed your system up by grounding pin 2C? Yet you seem to be getting good voltages per the FSM at the ECU from your sensors (I remember your postings on that ECU thread I had going). Interesting...
Look at the schematic, page 50-31. Follow the "ground" circuit at the bottom of the sensors.See where it connects in at the AFM? In between the pot and the intake air temp sensor resistor. Follow me so far? Now, at the top of that AFM drawing is the 5vref input, and in the middle of the pot is the wiper for the AFM input for the ECU.
Now, look at the intake air temp variable resistor at the bottom of the AFM. Spec input to pin 2J from that sensor is 2-3v at 68*F. In other words, that upper pot doesn't drop much voltage, because the bottom resistor has at least 3v+ output AFTER dropping the voltage at its beginning.
Now look at where that sensor "ground" circuit connects in- at the MIDDLE, between the pot and the resistor. That means 1) there has to be at least +4v at that point, and 2) it cannot possibly be a ground potential because of #1.
Most of the sensors would feel this as a negative voltage, closer to ground, because they have that 5vref input. But not the thermo sensor or the dynamic chamber intake air temp sensor. To them it's a positive voltage, because they have no 5vref input, and that's the power source for them (it also neatly explains why their voltage inputs to the ECU are so much lower than the 5vref sensors).
I have no idea why we sense a ground potential at pin 2C, it makes no sense...
I probably lost you halfway through my thesis, but that's how I see that thermo sensor working from just looking at the schematic...
That makes no sense, for a couple of reasons; one being that if the ECU is supplying 5v on that wire, there is no wire to return the signal back to the ECU after the voltage has been dropped by the thermo sensor. Another reason is that the FSM calls for .4 to 1.8v at idle (key on, obviously). Why read 5v with just the key on, yet read (say) 1.5v with the car idling, right after start? The sensor is still the same temp right after start, how does the voltage drop so much?
BTW, I see that I've recorded a 2.2v at that pin with key on, cold engine, at 75*F...
Another reason is that the FSM shows that green/white wire as being a signal return to the ECU from the thermo sensor, not a voltage supply (as is the brown/white 5vref wire at pin 2A).
Could you have perhaps screwed your system up by grounding pin 2C? Yet you seem to be getting good voltages per the FSM at the ECU from your sensors (I remember your postings on that ECU thread I had going). Interesting...
Look at the schematic, page 50-31. Follow the "ground" circuit at the bottom of the sensors.See where it connects in at the AFM? In between the pot and the intake air temp sensor resistor. Follow me so far? Now, at the top of that AFM drawing is the 5vref input, and in the middle of the pot is the wiper for the AFM input for the ECU.
Now, look at the intake air temp variable resistor at the bottom of the AFM. Spec input to pin 2J from that sensor is 2-3v at 68*F. In other words, that upper pot doesn't drop much voltage, because the bottom resistor has at least 3v+ output AFTER dropping the voltage at its beginning.
Now look at where that sensor "ground" circuit connects in- at the MIDDLE, between the pot and the resistor. That means 1) there has to be at least +4v at that point, and 2) it cannot possibly be a ground potential because of #1.
Most of the sensors would feel this as a negative voltage, closer to ground, because they have that 5vref input. But not the thermo sensor or the dynamic chamber intake air temp sensor. To them it's a positive voltage, because they have no 5vref input, and that's the power source for them (it also neatly explains why their voltage inputs to the ECU are so much lower than the 5vref sensors).
I have no idea why we sense a ground potential at pin 2C, it makes no sense...
I probably lost you halfway through my thesis, but that's how I see that thermo sensor working from just looking at the schematic...
03-15-05, 07:43 PM
#40
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You guys are insanely good at this.
I am having quite a shitty time now... and I'm late to work. =(
So ALL I DID was splice open that 3D ground wire at the ECU (in the S5 schematics that is the "ground" gangbang for the sensors... they all go to 3D) and spliced in a wire that went to the black/brown wire on the thermosensor (the wire I spliced was also black/brown also, so I was confident that it is the right one).
Went to turn the car on... got nothing, something was draining the battery bad.
Now, I have had the FEELING that something the last week or two has been draining on the battery unnecessarily... I don't know if it was the thermosensor wiring I did or WHAT.
But basically it just acted like it didn't have enough power to turn the thing over. Voltage was low. I hooked up a jumper... it cranks fine.
It just won't start... my personal guess... no spark...it's electrical, I know I'm getting fuel (can smell it after cranking a long time) and air... plus there is no reason either of those would be gone, I was driving the car earlier today.
I hooked up the test lead and what do I get?
The check engine light turns off for a second... then when it would normally FLASH the codes... it's just SOLID. I made sure it's jumpered... so it's in test mode, WTF causes it to just stay SOLID?? Intuition tells me thats very bad. ;(
--Gary
I am having quite a shitty time now... and I'm late to work. =(
So ALL I DID was splice open that 3D ground wire at the ECU (in the S5 schematics that is the "ground" gangbang for the sensors... they all go to 3D) and spliced in a wire that went to the black/brown wire on the thermosensor (the wire I spliced was also black/brown also, so I was confident that it is the right one).
Went to turn the car on... got nothing, something was draining the battery bad.
Now, I have had the FEELING that something the last week or two has been draining on the battery unnecessarily... I don't know if it was the thermosensor wiring I did or WHAT.
But basically it just acted like it didn't have enough power to turn the thing over. Voltage was low. I hooked up a jumper... it cranks fine.
It just won't start... my personal guess... no spark...it's electrical, I know I'm getting fuel (can smell it after cranking a long time) and air... plus there is no reason either of those would be gone, I was driving the car earlier today.
I hooked up the test lead and what do I get?
The check engine light turns off for a second... then when it would normally FLASH the codes... it's just SOLID. I made sure it's jumpered... so it's in test mode, WTF causes it to just stay SOLID?? Intuition tells me thats very bad. ;(
--Gary
03-15-05, 07:49 PM
#41
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Crap, let me add a few things I've already done to diagnose...
I assumed I might have fried the ECU, but I have a working backup one. So I cut open the splices I made, I checked all the connections for continuity... they were all fine... so I went and disconnected the wire between the 3D pin and the thermosensor. This should have returned the circuit to its FORMER glory of just not working, but the car was still running fine like this... just minus the thermosensor. So I got nothing on that. Not wanting to risk THAT wiring with the ECU... I took off the thermosensor plug ALTOGETHER. It couldn't possibly hurt the ECU to have the wiring with the thermosensor unplugged.
Swapped the ECU... got the same exact thing... SOLID on light for check.
I'm stumped.
--Gary
I assumed I might have fried the ECU, but I have a working backup one. So I cut open the splices I made, I checked all the connections for continuity... they were all fine... so I went and disconnected the wire between the 3D pin and the thermosensor. This should have returned the circuit to its FORMER glory of just not working, but the car was still running fine like this... just minus the thermosensor. So I got nothing on that. Not wanting to risk THAT wiring with the ECU... I took off the thermosensor plug ALTOGETHER. It couldn't possibly hurt the ECU to have the wiring with the thermosensor unplugged.
Swapped the ECU... got the same exact thing... SOLID on light for check.
I'm stumped.
--Gary
03-15-05, 08:01 PM
#42
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Bob, did you add that wire at 3D only for the thermo sensor, or did you also keep all of the other sensors attached into the circuit?
This is really strange, I thought I knew this sensor system well, but now I'm trying to understand these new revelations, lol...
Yeah, the ECU should fall back on its internal fail-safe map if it loses the thermo sensor's input, I would think. Then again, when mine went bad (the connector on the sensor had cracked) during driving it was like the car went into a limp mode or something- all engine power lost for a couple of seconds, then everything back to normal again...
Is the sensors' circuit the same on the S5's? Anybody know?
This is really strange, I thought I knew this sensor system well, but now I'm trying to understand these new revelations, lol...
Yeah, the ECU should fall back on its internal fail-safe map if it loses the thermo sensor's input, I would think. Then again, when mine went bad (the connector on the sensor had cracked) during driving it was like the car went into a limp mode or something- all engine power lost for a couple of seconds, then everything back to normal again...
Is the sensors' circuit the same on the S5's? Anybody know?
03-15-05, 08:12 PM
#43
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Yeah, I just cut off the wire jacket for about 1/8" near the plug, wrapped the connecting wire around it and taped it up. The only thing that changed was instead of the thermosensor being grounded, it would go into that "ECU ground" that 3D is.
I'm totally lost... there is NO WAY what I did could have caused such a huge problem. So what else can I check?
Why would the ECU light stay SOLID instead of flashing codes? Does that mean there ARE no codes or what??
--Gary
I'm totally lost... there is NO WAY what I did could have caused such a huge problem. So what else can I check?
Why would the ECU light stay SOLID instead of flashing codes? Does that mean there ARE no codes or what??
--Gary
03-15-05, 08:46 PM
#44
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Dude, I don't know about the S5 ECUs....
Definetly remove all of the add-on wiring you did, and start again from scratch...The thermo sensor circuit by itself is very simple, notwithstanding all of the discussions we've been having on it (civil discussions at that, lol).
I wonder if somehow the sensor itself is shorting to ground, and that's why its not behaving when you try to get the wiring back to OEM specs?
Just don't know what to tell ya, if it was me I'd run all new wiring from the ECU to the thermo sensor, then to that "gang" circuit (might have to unwrap some tape to figure out where it splices into the harness).
What are the rest of your sensors doing with the key on? Everything in spec at the ECU pins, besides the thermo sensor?
Definetly remove all of the add-on wiring you did, and start again from scratch...The thermo sensor circuit by itself is very simple, notwithstanding all of the discussions we've been having on it (civil discussions at that, lol).
I wonder if somehow the sensor itself is shorting to ground, and that's why its not behaving when you try to get the wiring back to OEM specs?
Just don't know what to tell ya, if it was me I'd run all new wiring from the ECU to the thermo sensor, then to that "gang" circuit (might have to unwrap some tape to figure out where it splices into the harness).
What are the rest of your sensors doing with the key on? Everything in spec at the ECU pins, besides the thermo sensor?
03-15-05, 08:53 PM
#45
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Man, I just re-read the first page of the thread (the stuff before a couple of insane guys hijacked it, lol), and I'm still unsure if you S5 guys have a SEPERATE 5v input to that bad boy, or if it's wired like the S4's. Did YOU ever figure that out????
03-15-05, 09:14 PM
#46
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OKAYOKAYOKAY somehow one of the TOP ECU plugs (out of sight) came out, that was the problem... *SIGH*
Gotta get to work, I'll update later!! Thanks Wayne!
--Gary
Gotta get to work, I'll update later!! Thanks Wayne!
--Gary
03-16-05, 01:00 AM
#47
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Alright, I THINK it worked.
Driving around, the car is MUUUUUUCH better at not sounding like a JGTC car.
Unfortunately this means everyone and their ******* GRANDMOTHER thinks they can take me... and pulls up next to me on the freeway being ****.
*sigh*
Maybe I'll keep that wire open so I can make this thing sound like a JGTC car so people aren't f'ing retarded all the time.
Anyway... the reason I say I _THINK_ it worked is because I think my logicon is screeeeewed. It doesn't reset... now at first I kept thinking "Why won't the ECU reset?!" but that isn't the problem, the LOGICON is what throws the codes right? So if it fries it will always have the same codes right?
So I'm still getting the code 9, BUT the car is running better... which implies the ECU now sees that it's there.
--Gary
Driving around, the car is MUUUUUUCH better at not sounding like a JGTC car.
Unfortunately this means everyone and their ******* GRANDMOTHER thinks they can take me... and pulls up next to me on the freeway being ****.
*sigh*
Maybe I'll keep that wire open so I can make this thing sound like a JGTC car so people aren't f'ing retarded all the time.
Anyway... the reason I say I _THINK_ it worked is because I think my logicon is screeeeewed. It doesn't reset... now at first I kept thinking "Why won't the ECU reset?!" but that isn't the problem, the LOGICON is what throws the codes right? So if it fries it will always have the same codes right?
So I'm still getting the code 9, BUT the car is running better... which implies the ECU now sees that it's there.
--Gary
03-16-05, 10:55 AM
#48
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The logicon only operates the heater/airconditioner/blower motor. Nothing to do with the ECU and the codes the ECU puts out.
There's a procedure in the series five fsm that resets the ECU. I don't know how, I'm series four oriented. I think you take the battery terminals off for a short period of time and maybe step on the brake pedal while their off, then reinstall the battery terminals. Something like that. I'd check the series five fsm.
There's a procedure in the series five fsm that resets the ECU. I don't know how, I'm series four oriented. I think you take the battery terminals off for a short period of time and maybe step on the brake pedal while their off, then reinstall the battery terminals. Something like that. I'd check the series five fsm.
03-16-05, 01:37 PM
#49
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Yeah I've reset the ECU a million times, did the same thing I do every time and it didn't work... I'll check the FSM anyway.
But I used the wrong term, by logicon I was thinking of the panel with all the warning lights, where the check engine light is... if that was fried it would always show the same codes right?
--Gary
But I used the wrong term, by logicon I was thinking of the panel with all the warning lights, where the check engine light is... if that was fried it would always show the same codes right?
--Gary
03-16-05, 02:02 PM
#50
Lives on the Forum
Gary, have you even figured out what a code "9" is for your car?
Check for more plugs being disconnected
Get down there to the ECU and read out EVERYTHING per the chart/table/whatever that should be in your FSM (fuel/ECU section). If the ECU still seems a bit screwy, that means that an input or output ain't right. The only way you're going to know for sure is to get down there and start reading some voltages (and the grounds-but use voltage for these, power on, and make sure you're getting ZERO volts to a good ground from all of the ECU grounds...). Later on you can go to resistance with power off and re-read the grounds, if you wish...
Check for more plugs being disconnected
Get down there to the ECU and read out EVERYTHING per the chart/table/whatever that should be in your FSM (fuel/ECU section). If the ECU still seems a bit screwy, that means that an input or output ain't right. The only way you're going to know for sure is to get down there and start reading some voltages (and the grounds-but use voltage for these, power on, and make sure you're getting ZERO volts to a good ground from all of the ECU grounds...). Later on you can go to resistance with power off and re-read the grounds, if you wish...