P0689
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Instructor
Joined: Aug 2015
Posts: 145
Likes: 4
P0689
Car has been running great these last couple of months but while driving to work today sped up to pass somebody and car went into limp mode. Reduced engine power came on along with a check engine light. While on lunch went to oreillys to get the code checked and its a p0689 code. Looked it up but not really getting anywhere. Wondering if any of you have experieced this and what was the problem/fix? Car is a 05 btw
Instructor
Joined: Mar 2013
Posts: 122
Likes: 5
From: Maryland
OBD2-OBDII Codes
P0689 CHEVROLET - Electronic Control Module Power Relay Sense Circuit Low
Possible causes
- Weak battery - Low voltage while cranking
- Faulty Engine Control Module (ECM) relay
- Blown ECM fuse
- Faulty ECM
- ECM harness is open or shorted
- ECM circuit poor electrical connection
P0689 CHEVROLET - Electronic Control Module Power Relay Sense Circuit Low
Possible causes
- Weak battery - Low voltage while cranking
- Faulty Engine Control Module (ECM) relay
- Blown ECM fuse
- Faulty ECM
- ECM harness is open or shorted
- ECM circuit poor electrical connection
Thread Starter
Instructor
Joined: Aug 2015
Posts: 145
Likes: 4
OBD2-OBDII Codes
P0689 CHEVROLET - Electronic Control Module Power Relay Sense Circuit Low
Possible causes
- Weak battery - Low voltage while cranking
- Faulty Engine Control Module (ECM) relay
- Blown ECM fuse
- Faulty ECM
- ECM harness is open or shorted
- ECM circuit poor electrical connection
P0689 CHEVROLET - Electronic Control Module Power Relay Sense Circuit Low
Possible causes
- Weak battery - Low voltage while cranking
- Faulty Engine Control Module (ECM) relay
- Blown ECM fuse
- Faulty ECM
- ECM harness is open or shorted
- ECM circuit poor electrical connection
Well checked all my wiring to make sure i didn't have a loose cable or anything. Battery on dash says its at a solid 14.1-14.3. Althought when you start it up it does hang at about 10.0 for a couple of seconds. Might just replace the battery see if that does the trick. I dont think it'd start if it was something related to the ECM.
Last edited by aAZz; Dec 12, 2015 at 11:12 AM.
