Calling the wiring diagram guru's!
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Calling the wiring diagram guru's!
HAILERS I need your help! You helped me with this once before, but I was many miles away from my car and didn't have a chance to do it, and I can't find the diagram again! I need the clutch switch (the annoying one that screws with your idle) diagram from a s5, and which pin it is on the ECU, and what voltage it see's when it's open/closed 
Though, if you're not HAILERS and you feel like helping, please do, I'll be just as happy!
Though, if you're not HAILERS and you feel like helping, please do, I'll be just as happy!
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Ahh, in body electrical it talks about a 5v for cruise. I believe it's a 4 wire switch running both the ECU & cruise. Thanks rat, now I just need to find out what else it's tied into! Where's hailers when you need him to scan a page?
You can download the FSM at www.FC3s.org 
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By that, I'm assuming you mean one side of the switch is grounded, and the ECU pushes 12v to the switch, and when the switch is activated, it grounds?
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Ok, that makes a little more sense, I'll have to verify on the other car if it's grounded or not, wouldn't want to burn out my ECU before doing this. Thanks Icemark
HAILERS
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I'm at work. I thought that when you pushed the clutch OR the brake pedal in, that you put 12v on a pin at the cruise control unit. That should disengage the cruise control if it was engaged.
I visited the fsm online and its got me confused. I downloaded two diagrams, one from a page T-70 a series five, and another but I think I got that from a 88 wiring diagram. They disagree a bit. Confused. Must be a series four vs a series five deal. If I think of it I'll jpg a series five schematic when I get home. That in itself is a problem on this site.
So, what's wrong with your cruise anyway? Not disengaging? Or not engaging?
I visited the fsm online and its got me confused. I downloaded two diagrams, one from a page T-70 a series five, and another but I think I got that from a 88 wiring diagram. They disagree a bit. Confused. Must be a series four vs a series five deal. If I think of it I'll jpg a series five schematic when I get home. That in itself is a problem on this site.
So, what's wrong with your cruise anyway? Not disengaging? Or not engaging?
Last edited by HAILERS; May 8, 2003 at 10:16 PM.
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Screw the cruise, it's the ECU i have problems with My car doesn't have cruise, I just need to figure out wether i should send it 12v, or if I should ground it, and I'm not having much luck figuring out which! It'd be pretty easy if someone went out to their series 5 car with a multimeter and checked :-D
My car doesn't have cruise, I just need to figure out wether i should send it 12v, or if I should ground it, and I'm not having much luck figuring out which! It'd be pretty easy if someone went out to their series 5 car with a multimeter and checked :-D
HAILERS
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From: FORT WORTH, TEXAS,USA
I look at the pinout on the ECU in the 89 manual online and the way I read it, when you depress the clutch pedal, you put a ground on pin 1Q on the ECU. When you release the pedal, the ground goes away and you would see 12v on a meter if it was connected to the ECU at pin 1Q. That is just 12v inside the ECU, not coming from anywhere else.
If I remember right, this is not the same as on my series four. I'll look at it when I can.
Yeah, on a series four, if you step on the clutch pedal, you PUT 12v on the ECU. If you let off the pedal, you open that circuit and nothing is put on the ECU pin (different pin on a series four. Its pin 1L on a series four. Pin 1Q on a series five.)
If I remember right, this is not the same as on my series four. I'll look at it when I can.
Yeah, on a series four, if you step on the clutch pedal, you PUT 12v on the ECU. If you let off the pedal, you open that circuit and nothing is put on the ECU pin (different pin on a series four. Its pin 1L on a series four. Pin 1Q on a series five.)
Last edited by HAILERS; May 8, 2003 at 10:42 PM.
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That'd be nice, I'm digging through the s4 FSM to see what it has as well. Thanks for the help, you tend to pop up in anything that begins with elec*
HAILERS
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From: FORT WORTH, TEXAS,USA
I edited my last post as you wrote the post above. You might take a look.
By the way. Is your idle altered when you put the clutch pedal in, but it only does this when the car is cold? Or does it alter your idle anytime you put the clutch pedal in, hot or cold???
By the way. Is your idle altered when you put the clutch pedal in, but it only does this when the car is cold? Or does it alter your idle anytime you put the clutch pedal in, hot or cold???
Last edited by HAILERS; May 8, 2003 at 10:44 PM.
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Ok, so on a series 4, the switch has a 12v feed which gets sent to the ECU when pressed? And on the series 5 the ECU is just looking for a ground signal when pressed? I think I'll stick a dmm on 1Q and see what it's reading.
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Hailers: I believe it does it all the time, but I'm not positive, usually by the time the cars warmed up my OMP tossed it's error code and I just turn it off since I can't do much more with it.
HAILERS
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From: FORT WORTH, TEXAS,USA
****Ok, so on a series 4, the switch has a 12v feed which gets sent to the ECU
when pressed? And on the series 5 the ECU is just looking for a ground
signal when pressed? I think I'll stick a dmm on 1Q and see what it's
reading.****
Yes. That's the way I see it. I'd take the plug off the ECU and get on pin 1Q on the plug. Then put the meter on ohms and step on the pedal. I think you'll see a ground when you do that. Should anyway if the diagram on the cruise is right and the pinout on the ECU is written right.
when pressed? And on the series 5 the ECU is just looking for a ground
signal when pressed? I think I'll stick a dmm on 1Q and see what it's
reading.****
Yes. That's the way I see it. I'd take the plug off the ECU and get on pin 1Q on the plug. Then put the meter on ohms and step on the pedal. I think you'll see a ground when you do that. Should anyway if the diagram on the cruise is right and the pinout on the ECU is written right.
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Alright, I'm going to have to run the wire anyway, unless I can figure out where that pin goes on an automatic car's harness. So, just run a ground to the switch, and run a line off to pin 1Q and I should be set?
HAILERS
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From: FORT WORTH, TEXAS,USA
Attached a foggy diagram showing the clutch sw and how when it makes, it makes a circuit to ground. Its difficult to scan out of the small fsm books. Have fun.
http://www.teamfc3s.org/forum/showth...threadid=13142
http://www.teamfc3s.org/forum/showth...threadid=13142
Last edited by HAILERS; May 9, 2003 at 10:43 AM.