Stabilirak Off, Traction Control Off, Engine Light On, Into limp Mode - In that order, while driving

[Joseph Garcia]

This has happened to me twice in a row (once on the highway, and once in city traffic), and I'm looking for suggestions regarding identifying root cause, or troubleshooting suggestions from the knowledgeable folks here on the Forum. Between the first and second failures, I replaced the batteries, so that potential cause has already been ruled out.

Here is the situation and trouble codes:

2007 yukon xl denali cruising down the road, when the Stabilitrak Off warning starts flashing. Shortly thereafter, the Traction Control Off warning starts flashing, also. Shortly thereafter, the engine warning light comes on, and the truck goes into limp mode. Scanner shows the following trouble codes (No existing trouble codes, prior to this occurrence.)


ECM 8 codes
U0140 - Lost communication with the BCM
U0121 - Lost communication with the ABS control module
U0101 - Lost communication with the TCM
P0700 - TCM requested MIL illumination
U0101 - Lost communication with TCM
U0140 - Lost communication with the BCM
U0100 - Lost communication with the ECM/PCM A
C0242 - PCM indicated TCS malfunction

EBCM 5 codes
U0140 - Lost communication with the BCM
U0121 - Lost communication with the ABS module
U0101 - Lost communication with the TCM
P0700 - tcm requested MIL illumination
U0101 - Lost communication with the TCM


ESC - Electronic Suspension Control Module 3 codes
U0140 - Lost communication with the BCM
U0121 - wasp communication with the ABS module
U0101 - Lost communication with the TCM


TCM 2 codes
U0140 - Lost communication with the BCM
U0121 - Lost communication with the ABS module


BCM 1 code
U0140 - Lost communication with the BCM


Rollover Sensor 1 code
U0140 - Lost communication with the BCM

 

[Fless]

Bump for visibility

 

[Marky Dissod]

I'm not an 'authority' on this, but whenever any of the vehicles in any of the taxi fleets I've ever worked with suffered several codes at once or in rapid succession,
EVERY grounding was removed, cleaned, lightly resurfaced, and reinstalled, and to clean each connector to every module that coded PRIOR to troubleshooting.
(Kinda like 'Tap-Rack'Bang' before 'SPORTS'.) More often than not, the codes did not reappear after the above steps were taken.

 

[rdezs]

I'd also check the resistance on the battery cables. They tend to fail from within, and that definitely looks like a connection issue somewhere

 

[Joseph Garcia]

Thank you for your replies. Much appreciated.

I checked the battery cables, and they are good from a resistance standpoint.

I am in the process of checking/cleaning grounds now. In fact, I'm on my way out into the garage now to continue that process, which I started yesterday.

 

[solli5pack]

That many codes at once makes me think a bad ground somewhere.

 

[Fless]

Do more than a resistance test on the cables and connections -- do a voltage drop test to verify that they can handle a high amp load.

 

[Joseph Garcia]

Do more than a resistance test on the cables and connections -- do a voltage drop test to verify that they can handle a high amp load.

Will do.

 

[PG01]

Definitely ground Joe. Its been raining a ton here in NY and I believe you’re getting it as well so i wouldn’t doubt your neg batt cable is fubar or a ground on the frame under the drivers door…