ECM no communication
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ECM no communication I have a 2012 chevy tahoe LT, full rebuild inside and out! After it was completed , I test drove for 2 days probably 5 hours of driving it around the area. it killed as soon as i pulled up to my home and check engine light disappeared. wouldnt even turn over with key to start position
scanner will not communicate with ECM only, so checking the voltage of X1 ecm connector there is no power to pin #47 on ignition. Is this a BAD ECM
scanner will not communicate with ECM only, so checking the voltage of X1 ecm connector there is no power to pin #47 on ignition. Is this a BAD ECM
You may have a fuse block issue. The Trailblazers are notorious for this. There are solid wire traces inside there and they will typically crack in the same spot disabling the powertrain relay control.
Pull the powertrain relay out and see where pins 85 and 86 go into the fuse block. One of those two should have B+ voltage. The other one should show less than 5 ohms to ECM X1 Pin 59 (Yellow Wire).
Pull the powertrain relay out and see where pins 85 and 86 go into the fuse block. One of those two should have B+ voltage. The other one should show less than 5 ohms to ECM X1 Pin 59 (Yellow Wire).
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i'll just give you an update, changed the ECM and the issue was fixed!!! That was it 
But now the new ECM (reman haha) has its own problem, TAC-issue's/throttle sensor high voltage codes 1&2. Now in reduced power mode
I already have the replacement computer on the way "again"! Thanks for your help by the way
But now the new ECM (reman haha) has its own problem, TAC-issue's/throttle sensor high voltage codes 1&2. Now in reduced power mode
I already have the replacement computer on the way "again"! Thanks for your help by the way
