c4
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The TPS should be set to 0.54 volts, not 5.4 volts. I assume that was a typo...
Actually, the reference voltage for the TPS is 5.0 volts, so you couldn't get to 5.4 volts anyway.
Just to check everything, ground your meter to some metal part of the engine. Back probe the TPS connector while it is connected to the TPS. Ignition on.
Measure the top TPS wire (should be 5 volts).
Measure the middle wire (should be 0.54 volts at idle -- throttle closed).
Measure the bottom wire (should be zero volts -- ground).
How did you determine the TPS signal wasn't getting to the ECM? Did you measure it? Did you use a scanner? Did you get an error code? Some other way I didn't think of?
Actually, the reference voltage for the TPS is 5.0 volts, so you couldn't get to 5.4 volts anyway.
Just to check everything, ground your meter to some metal part of the engine. Back probe the TPS connector while it is connected to the TPS. Ignition on.
Measure the top TPS wire (should be 5 volts).
Measure the middle wire (should be 0.54 volts at idle -- throttle closed).
Measure the bottom wire (should be zero volts -- ground).
How did you determine the TPS signal wasn't getting to the ECM? Did you measure it? Did you use a scanner? Did you get an error code? Some other way I didn't think of?
Advanced
Joined: May 2010
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ECM wiring
http://www.google.com/imgres?imgurl=...QEwAA&dur=3647
Team Owner
Joined: Aug 2005
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From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
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Thread Starter
Intermediate
Joined: Aug 2013
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[QUOTE=Cliff Harris;1584731420]The TPS should be set to 0.54 volts, not 5.4 volts. I assume that was a typo...
Actually, the reference voltage for the TPS is 5.0 volts, so you couldn't get to 5.4 volts anyway.
Just to check everything, ground your meter to some metal part of the engine. Back probe the TPS connector while it is connected to the TPS. Ignition on.
Measure the top TPS wire (should be 5 volts).
Measure the middle wire (should be 0.54 volts at idle -- throttle closed).
Measure the bottom wire (should be zero volts -- ground).
How did you determine the TPS signal wasn't getting to the ECM? Did you measure it? Did you use a scanner? Did you get an error code? Some other way I didn't think of?[/QUOTE
yes i got a code 21 but the light will go off than will come back on i really think the ecm is bad when the light is off the car runs fine when the light is on the car bogs down and it loses power like it miss fire and pinging i did change the pig tale and the volts was 5.4 on the top one and 5.4 on the middle the bottom was 0 unless my meeter is bad but i just got it and i got the code by the a and b port when i turn the key on first i got a 12 and it flashed 3 times then i got 21 the service light keeps going on and off
Actually, the reference voltage for the TPS is 5.0 volts, so you couldn't get to 5.4 volts anyway.
Just to check everything, ground your meter to some metal part of the engine. Back probe the TPS connector while it is connected to the TPS. Ignition on.
Measure the top TPS wire (should be 5 volts).
Measure the middle wire (should be 0.54 volts at idle -- throttle closed).
Measure the bottom wire (should be zero volts -- ground).
How did you determine the TPS signal wasn't getting to the ECM? Did you measure it? Did you use a scanner? Did you get an error code? Some other way I didn't think of?[/QUOTE
yes i got a code 21 but the light will go off than will come back on i really think the ecm is bad when the light is off the car runs fine when the light is on the car bogs down and it loses power like it miss fire and pinging i did change the pig tale and the volts was 5.4 on the top one and 5.4 on the middle the bottom was 0 unless my meeter is bad but i just got it and i got the code by the a and b port when i turn the key on first i got a 12 and it flashed 3 times then i got 21 the service light keeps going on and off
Last edited by gremlin12; Aug 26, 2013 at 03:10 AM.
Thread Starter
Intermediate
Joined: Aug 2013
Posts: 27
Likes: 0
Look at your TPS connection to ECM in this link. Then if need be, run your own wiring to the proper ECM pins.
http://www.google.com/imgres?imgurl=...QEwAA&dur=3647
http://www.google.com/imgres?imgurl=...QEwAA&dur=3647
Last edited by gremlin12; Aug 26, 2013 at 03:00 AM.
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From: Houston Texas
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Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
The ECM is mounted in a tan plastic bracket that is bolted to the firewall under the dash on the passenger side. Take off the passenger side kick panel (several 7mm screws) to get to it. The ECM is held in the bracket by two 10mm bolts. You must remove the two connectors to get the ECM out. The connectors have latches that must be released to remove the connectors. Earlier connectors have a metal latch that must be pried up to release it. Later connectors have a plastic latch with a handle that you squeeze to release.
Here's a "top view" with the dash pad off. The two black pointy things are part of the ECM. They guide the ECM into position. The tan rectangle is the ECM bracket:
Here's a "top view" with the dash pad off. The two black pointy things are part of the ECM. They guide the ECM into position. The tan rectangle is the ECM bracket: