help with s5 turbo running on one rotor
09-30-14, 03:08 PM
#26
While checking the pins at the ecu I'm assuming with a multimeter probing the pin at the ecu and the other end of probe goes to a ground source? Yeah no check engine light and even removed the idiot cluster to check if there was a missing bulb with no luck. I'll check all of the recommemddatios and report back. Thanks
If you're getting spark then you should focus on fuel. Pin 3Y (Light Green wire) is the rear primary injector and pin 3Z (Light Green wire) is the rear secondary injector. W/key to on they should both have 12 volts. W/key to start they should have close to 8 volts or so. You might also want to unplug the boost sensor and see if this makes a difference in the rear rotor working or not. You can also unplug the TPS to see if it helps any. Both these sensors will cause fuel cut to the rear rotor under certain situations and perhaps one is playing a role in your problem. And have you checked for error codes? If the warning light cluster does not have the CEL light then it means it is a JDM.
If an LED light were connected to pin 3Z and pin 1B then w/key to start the light should flicker repeatedly indicating the ECU is triggering the injector properly. Same thing can be done for the other rear injector. And you should place the injectors back to their normal position if you have not already done so.
If an LED light were connected to pin 3Z and pin 1B then w/key to start the light should flicker repeatedly indicating the ECU is triggering the injector properly. Same thing can be done for the other rear injector. And you should place the injectors back to their normal position if you have not already done so.
09-30-14, 03:13 PM
#27
The ECU mounting bolts are a good ground source.
That you have no check light points back to a JDM ECU being mated w/the USDM harness. I know you stated it worked fine for 6 months and then you had problems but perhaps that's the problem created when mating the two different systems. I know there is a problem mating the two but what I do not know is if the problem is one in which comes and goes or it's always a problem. Someone else would need to chime in on this possibility.
That you have no check light points back to a JDM ECU being mated w/the USDM harness. I know you stated it worked fine for 6 months and then you had problems but perhaps that's the problem created when mating the two different systems. I know there is a problem mating the two but what I do not know is if the problem is one in which comes and goes or it's always a problem. Someone else would need to chime in on this possibility.
09-30-14, 05:02 PM
#29
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the JDM ECU will spit out codes, however it cannot drive the light bulb from the check engine light, so you need to plug an LED into the diagnostic connector on the shock tower.
it must be an LED, a regular bulb wont work.
if you're looking head on into the diag port its the top center (blk/white, power) and the top left (yellow/blue).
this works on the US and JDM ecus
it must be an LED, a regular bulb wont work.
if you're looking head on into the diag port its the top center (blk/white, power) and the top left (yellow/blue).
this works on the US and JDM ecus
09-30-14, 05:49 PM
#30
the JDM ECU will spit out codes, however it cannot drive the light bulb from the check engine light, so you need to plug an LED into the diagnostic connector on the shock tower.
it must be an LED, a regular bulb wont work.
if you're looking head on into the diag port its the top center (blk/white, power) and the top left (yellow/blue).
this works on the US and JDM ecus
it must be an LED, a regular bulb wont work.
if you're looking head on into the diag port its the top center (blk/white, power) and the top left (yellow/blue).
this works on the US and JDM ecus
09-30-14, 11:32 PM
#32
Update: Looks like I have the issue pinpointed. I sprayed carb cleaner in the vacuum port from brake booster to upper intake manifold and instantly the power sounded restored to rotor #2. I then removed the uim to recheck signal to the primary connectors this time with a test light probing into directly to the connector, its confirmed while spinning the cas gear there's only a flashing signal from rotor #1 and nothing from #2.
I did the same test this time from the ecu pins 3w there's a flashing signal and 3y nothing. I also tried checking for voltage on both pins at the ecu with the key in the on position, both with the same result, only getting .4 volts for a second then goes to 0 volts. I haven't test with the engine running yet.
Both of these test have been done with the current ecu and a spare ecu I just purchased. I have not checked tps or pressure sensor as I'm not sure if that still needs to be checked.
I did the same test this time from the ecu pins 3w there's a flashing signal and 3y nothing. I also tried checking for voltage on both pins at the ecu with the key in the on position, both with the same result, only getting .4 volts for a second then goes to 0 volts. I haven't test with the engine running yet.
Both of these test have been done with the current ecu and a spare ecu I just purchased. I have not checked tps or pressure sensor as I'm not sure if that still needs to be checked.
10-01-14, 12:19 AM
#33
If the ECU injector pins don't register 12 volts w/key to on then the injector plugs are not secured to the injectors properly or a wire within the plug is pulled back and not making proper contact w/the injector. If you don't get the proper voltage w/key to on then it won't read right w/key to start so it's likely a waste of time in doing so. The Black/Yellow wire at each injector supplies the 12 volts w/key to on that gets passed on to the Green wires that run to the ECU that you were checking for 12 volts on. If the B/Y wire has 12 volts then so should the Green based wire when the plug is connected to the injector (when pulled off the Green wire would have 0 voltage).
And I would forget about unplugging the two sensors for now and focus on the injector plugs themselves.
And a thing of note, only the primary injectors work when idling and while driving not under load and below 3800 rpm, thus checking the secondary injector(s) w/key to start won't tell you much since the ECU will not trigger them to work. If you were idling the car you can trick the ECU into thinking the car was under load, which is accomplished by unplugging both the TPS and boost sensors. If your problem reveals itself just idling then focus first on the primary injector(s), namely the rear rotor.
And I would forget about unplugging the two sensors for now and focus on the injector plugs themselves.
And a thing of note, only the primary injectors work when idling and while driving not under load and below 3800 rpm, thus checking the secondary injector(s) w/key to start won't tell you much since the ECU will not trigger them to work. If you were idling the car you can trick the ECU into thinking the car was under load, which is accomplished by unplugging both the TPS and boost sensors. If your problem reveals itself just idling then focus first on the primary injector(s), namely the rear rotor.
Last edited by satch; 10-01-14 at 12:46 AM.
10-01-14, 01:19 AM
#34
Great info. I'll check the connectors and make sure they are secure.
If the ECU injector pins don't register 12 volts w/key to on then the injector plugs are not secured to the injectors properly or a wire within the plug is pulled back and not making proper contact w/the injector. If you don't get the proper voltage w/key to on then it won't read right w/key to start so it's likely a waste of time in doing so. The Black/Yellow wire at each injector supplies the 12 volts w/key to on that gets passed on to the Green wires that run to the ECU that you were checking for 12 volts on. If the B/Y wire has 12 volts then so should the Green based wire when the plug is connected to the injector (when pulled off the Green wire would have 0 voltage).
And I would forget about unplugging the two sensors for now and focus on the injector plugs themselves.
And a thing of note, only the primary injectors work when idling and while driving not under load and below 3800 rpm, thus checking the secondary injector(s) w/key to start won't tell you much since the ECU will not trigger them to work. If you were idling the car you can trick the ECU into thinking the car was under load, which is accomplished by unplugging both the TPS and boost sensors. If your problem reveals itself just idling then focus first on the primary injector(s), namely the rear rotor.
And I would forget about unplugging the two sensors for now and focus on the injector plugs themselves.
And a thing of note, only the primary injectors work when idling and while driving not under load and below 3800 rpm, thus checking the secondary injector(s) w/key to start won't tell you much since the ECU will not trigger them to work. If you were idling the car you can trick the ECU into thinking the car was under load, which is accomplished by unplugging both the TPS and boost sensors. If your problem reveals itself just idling then focus first on the primary injector(s), namely the rear rotor.
10-03-14, 11:57 PM
#35
I just re-read this qoute and realized when I tested the pinout at the ecu I did not have the injectors plugged in. I just re-tested with everything back together with the ignition set to on but the engine not running I was getting 9 volts from both 3W and 3Y pins at the ecu harness. Another observation I have noticed from previous testing i forgot to mention is both primary connectors have positive power signal, however for #2 rotor primary there's no ground signal which flashes for #1 rotor primary connector. Am I on the right track assuming the issue is ground? I also plugged in my ecu to a modified turbo s5 car and did verify at pins 3W and 3Y there's power with the key on and if I spin the CAS the signal flashes on both pins which I would imagine eliminates the possibility of a faulty ECU. Please correct me if im on the wrong thought process here.
If the ECU injector pins don't register 12 volts w/key to on then the injector plugs are not secured to the injectors properly or a wire within the plug is pulled back and not making proper contact w/the injector. If you don't get the proper voltage w/key to on then it won't read right w/key to start so it's likely a waste of time in doing so. The Black/Yellow wire at each injector supplies the 12 volts w/key to on that gets passed on to the Green wires that run to the ECU that you were checking for 12 volts on. If the B/Y wire has 12 volts then so should the Green based wire when the plug is connected to the injector (when pulled off the Green wire would have 0 voltage).
And I would forget about unplugging the two sensors for now and focus on the injector plugs themselves.
And a thing of note, only the primary injectors work when idling and while driving not under load and below 3800 rpm, thus checking the secondary injector(s) w/key to start won't tell you much since the ECU will not trigger them to work. If you were idling the car you can trick the ECU into thinking the car was under load, which is accomplished by unplugging both the TPS and boost sensors. If your problem reveals itself just idling then focus first on the primary injector(s), namely the rear rotor.
And I would forget about unplugging the two sensors for now and focus on the injector plugs themselves.
And a thing of note, only the primary injectors work when idling and while driving not under load and below 3800 rpm, thus checking the secondary injector(s) w/key to start won't tell you much since the ECU will not trigger them to work. If you were idling the car you can trick the ECU into thinking the car was under load, which is accomplished by unplugging both the TPS and boost sensors. If your problem reveals itself just idling then focus first on the primary injector(s), namely the rear rotor.
10-04-14, 09:11 AM
#36
So, if I understand this correctly, you have a flashing of the LED light to the front rotor primary injector but you do not get the same flashing to the rear rotor's primary injector w/key to start. Correct?
If this is the case then pull the plug off of the rear rotor primary injector and retest ECU pin 3Y (Light Green/Black wire) w/key to start and see if the light will now flash or not.
If this is the case then pull the plug off of the rear rotor primary injector and retest ECU pin 3Y (Light Green/Black wire) w/key to start and see if the light will now flash or not.
10-04-14, 09:32 PM
#37
just tested this and getting no flash at pin 3Y
So, if I understand this correctly, you have a flashing of the LED light to the front rotor primary injector but you do not get the same flashing to the rear rotor's primary injector w/key to start. Correct?
If this is the case then pull the plug off of the rear rotor primary injector and retest ECU pin 3Y (Light Green/Black wire) w/key to start and see if the light will now flash or not.
If this is the case then pull the plug off of the rear rotor primary injector and retest ECU pin 3Y (Light Green/Black wire) w/key to start and see if the light will now flash or not.
10-04-14, 10:45 PM
#38
Is this w/the plug connected to the injector though? If it is then try it w/o. And are you 100% sure you are checking the correct pin/wire?
And you should read 12 volts on the injector pins w/key to on and not 9 volts. Pin 1B (Black/White wire) should also read 12 volts w/key to on. Does it? Is your battery low? If your battery is good then perhaps you have a grounding problem.
And you should read 12 volts on the injector pins w/key to on and not 9 volts. Pin 1B (Black/White wire) should also read 12 volts w/key to on. Does it? Is your battery low? If your battery is good then perhaps you have a grounding problem.
Last edited by satch; 10-04-14 at 11:05 PM.
10-04-14, 11:05 PM
#40
also reading though a past post you mentioned the voltage goes from black yellow to green wire once the injector is plugged in? I was under the impression the two wires for the injector pigtail are power and ground but it does not appear that way now that im testing rotor 1 primary.
10-04-14, 11:31 PM
#41
Another test I just performed which I'm sure is basically the same has what is happening at the ecu. Took a voltmeter and tested from 1 pin to the other getting 12 volts that hold steady for rotor 1 primary pigtail, rotor #2 only provides up to 3 volts but drops to below 1 volt after 1 second of constant contact.
10-04-14, 11:43 PM
#42
also reading though a past post you mentioned the voltage goes from black yellow to green wire once the injector is plugged in? I was under the impression the two wires for the injector pigtail are power and ground but it does not appear that way now that im testing rotor 1 primary.
B/Y is always power w/key to on whether the plug is connected to the injector or not. The Green wire has voltage if the plug is connected w/key to on only because the voltage passes through the injector from B/Y to the Green wire. Once the plug is removed from the injector the voltage dies on the Green wire w/key to on. When everything is hooked up the ECU will take the voltage on the Green wire and reduces it to a ground signal pulse w/key to start which is what causes the LED light to flicker.
10-04-14, 11:54 PM
#43
would you advise me to remove the pin at the ecu harness and inspect at this point?
B/Y is always power w/key to on whether the plug is connected to the injector or not. The Green wire has voltage if the plug is connected w/key to on only because the voltage passes through the injector from B/Y to the Green wire. Once the plug is removed from the injector the voltage dies on the Green wire w/key to on. When everything is hooked up the ECU will take the voltage on the Green wire and reduces it to a ground signal pulse w/key to start which is what causes the LED light to flicker.
10-05-14, 12:00 AM
#44
You want to inspect the plug housing the pin to make sure the wire feeding into the back of the plug is not pulled back and then not making contact w/the ECU.
All of the 4 injector wires are Green. What specifically is the color of the wire you are looking at for pin 3Y?
All of the 4 injector wires are Green. What specifically is the color of the wire you are looking at for pin 3Y?
Last edited by satch; 10-05-14 at 12:06 AM.
10-05-14, 12:24 AM
#45
Pin 3Y for me is light green with a black stripe and red dots on the wire. Just removed the pin from the connector nothing looks out of the ordinary, when placing the pin back in the connector I still get the snap sound. I also tested continuity from the green wire at the injector pigtail to the ecu pin and there's not a problem with that. Is it safe to say there's something definitely going on with the connection?
10-05-14, 01:25 AM
#46
Not really sure as it could be a grounding issue. How about reading the ohms of the front rotor primary injector and then do the same for the rear rotor primary injector and see if they are the same.
And didn't you mention you put your ECU in another car and it read properly?
And didn't you mention you put your ECU in another car and it read properly?
10-05-14, 02:15 PM
#47
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just to add a clarification, the circuit looks like this;
battery -> main relay -> blk/yellow wire -> one of the fuses in the underhood fuse box -> injector -> ecu -> ground.
for the actual control logic, the ecu will trigger the injectors when it has power, ground and an rpm signal, unless it is having a failsafe cut of some kind.
the US T2 ecu has a boost limiter cut, and the JDM ecu has the same boost cut, AND a speed cut. there is also a condition where it cuts the fuel to the rear rotor under decel, although rpm needs to be in a certain range (1100-1750?)
so if we rule out a problem with the circuit, it could be a fuel cut. boost cut is done from the boost sensor. speed cut comes from the cluster, but i'm not sure which ecu pin it goes too
battery -> main relay -> blk/yellow wire -> one of the fuses in the underhood fuse box -> injector -> ecu -> ground.
for the actual control logic, the ecu will trigger the injectors when it has power, ground and an rpm signal, unless it is having a failsafe cut of some kind.
the US T2 ecu has a boost limiter cut, and the JDM ecu has the same boost cut, AND a speed cut. there is also a condition where it cuts the fuel to the rear rotor under decel, although rpm needs to be in a certain range (1100-1750?)
so if we rule out a problem with the circuit, it could be a fuel cut. boost cut is done from the boost sensor. speed cut comes from the cluster, but i'm not sure which ecu pin it goes too
10-05-14, 11:25 PM
#49
The engine ground (on top of the engine housing) serves as the grounds for the ECU. And you can try unplugging the TPS and boost sensor and see if this affects the ability of the injector driver on pin 3Y to work.
And you did previously state that pin 3Y had 9 volts w/key to on (even though it should have 12 volts)?
And you did previously state that pin 3Y had 9 volts w/key to on (even though it should have 12 volts)?
10-06-14, 12:31 AM
#50
I'll try disconnecting both tps and boost sensor and retest. Yeah both rotor 1 and 2 had the same voltage.
The engine ground (on top of the engine housing) serves as the grounds for the ECU. And you can try unplugging the TPS and boost sensor and see if this affects the ability of the injector driver on pin 3Y to work.
And you did previously state that pin 3Y had 9 volts w/key to on (even though it should have 12 volts)?
And you did previously state that pin 3Y had 9 volts w/key to on (even though it should have 12 volts)?