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Ask GM Tech (Cam) Your Own Question
GM Tech (Cam)
GM Tech (Cam), GMC Mechanic
Category: GM
Satisfied Customers: 29522
Experience:  GM Grand Master Technician 2007. 14 years experience.
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2003 Yukon: 4wd..stalling issues, with reduced power message coming

Customer Question

2003 Yukon, 4wd, "Z" code engine 5.3L.
Vehicle has stalling issues, with "reduced power" message coming on. Previously we replaced TAC Module and pigtail connector (wiring was damaged).
No vehicle is stalling again, throwing ABS light on and 4wd blinking lights. Plus CEL Light.
Codes for PCM-history, P1518, U1301.
Codes for BCM-history, U1000, U1305, U1016, U1160, U1096, U1152, B2752, B2961
Codes for EBCM-C0237, CO291
Codes for TCCM-history, U1255,U1000,C0300, CO305,CO306,CO321,CO327,CO359,CO374,
CO379,CO550,BO790,B2725, U1301
Where do I start?? Checked grounds-good, checked Ignition switch-fine. Customer complained vehicle shut down and wouldn't let them restart the car (theft system engaged?).
Chad Menconi, AA Automotive
Submitted: 6 years ago.
Category: GM
Expert:  GM Tech (Cam) replied 6 years ago.

Hi, I'm Cam. May I ask your first name?
I am working to get you a fast accurate answer. About your vehicle, if you clear the codes, do any come back?

Specifically what grounds?


Customer: replied 6 years ago.
Grounds to rear of cylinder head. No codes r
Expert:  GM Tech (Cam) replied 6 years ago.

Check the grounds under the drivers door on the frame. Take them off and clean them to bare metal. Then attach and assess this issue again.


Customer: replied 6 years ago.
Thanks Cam, Test drove the vehicle yesterday after checking PCM Connections and erasing all codes in BCM, PCM, TCCM and EBCM. Maybe 8 miles, rechecked codes, none found. This morning did the ground/repair you recommmended. Going to test drive more today or even give it back to the customer to have them test drive.
Expert:  GM Tech (Cam) replied 6 years ago.

OK is there more I can get you today?