...ran into this before? very intermittent, but causes reduced power light on dash. is also equipped with electronic throttle control, ( no throttle cable) that works on this circuit. havent been able to duplicate the problem while testing. help much needed!! sometimes codes come up for this system, but they will be caused by the low referance voltage problem.
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2003 gmc envoy, code p1635 (5v reference circuit problem) , intermittent. anyone...
- Thread starter lehewser
- Start date
Try inspecting the main engine wiring harness between the PCM and the generator assembly for a potential short to ground. There is a metal wiring harness retainer in this area that secures the main engine harness. If the harness conduit is mispositioned, some of the wiring may become exposed and chaff on the harness retainer. This may eventually cause the exposed circuit to short to ground. Inspect the 3 harnesses that connect to the PCM for potential shorts to ground on the metal PCM mounting bracket, just below the PCM. There are plastic harness retainers on the PCM bracket that secure the harnesses to the PCM bracket. If the harness conduit is mispositioned, some of the wiring may become exposed and chaff on the PCM bracket. This may eventually cause the exposed circuit to short to ground.
If a chaffed circuit is found in either of the above locations, repair the circuit. Once the circuit is repaired, tape the area of the affected area of the harness to prevent the wires from becoming exposed in the future and secure the harness using the original harness retainer.
Hope this helps,
Good Luck!
If a chaffed circuit is found in either of the above locations, repair the circuit. Once the circuit is repaired, tape the area of the affected area of the harness to prevent the wires from becoming exposed in the future and secure the harness using the original harness retainer.
Hope this helps,
Good Luck!