PIT5405A

Bulletin No.: PIT5405A
Date: Nov-2015
Subject:
Reduced Power Steering Assist Engine Stall IPC / Radio / HVAC Goes Blank Various DTCs
Models:
2015-2016 Cadillac Escalade Models
2014 Chevrolet Silverado 1500
2015-2016 Chevrolet Silverado, Suburban, Tahoe
2014 GMC Sierra 1500
2015-2016 GMC Sierra, Yukon Models
This PI was superseded to add 2016 Models and update Recommendation. Please discard PIT5405.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Some owners may comment of any of the following issues:
–
Reduced power steering assist (only LD models equipped with electric power steering)
–
Engine stall
–
IPC going blank or inoperative
–
Radio/ICS going blank
–
HVAC going blank
–
Hood ajar message and/or dome lamps flash when shifting into reverse
–
Alarm sounds when locking doors
–
Wipers continue to run for a short time after turning off and then stop/park in the incorrect location
–
Any of the following DTCs: U0073, U0078, U0029, U0028, U0415, U0140, U0126, U0121, U0101, U0100, C0544, U1510, U0073, B127B, B2605, B3600,
C0800, U0428, U0452 and P0513
These concerns could be caused by any of the three following issues:
1.
. A poor BCM ground at G218.
2.
A shorted B+ Battery cable at the Starter Solenoid.
3.
High resistance/loose connection at the battery fuse block or battery cables
Recommendation/Instructions
To correct these concerns:
1.
Inspect G218 for a loose connection or the front of dash insulator mat (2) for being trapped between the ground eyelet and the body/stud as shown
below (1). If the dash insulator mat is trapped, cut the mat away from the ground stud so it will no longer interfere. Reinstall the ground eyelet, the nut,
and retighten.
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2.
Inspect the B+ battery cable at the starter solenoid for shorting out on the starter heat shield, as shown below. If the battery cable is shorting on the
starter heat shield, replace the B+ battery cable and starter heat shield. After installing the new starter heat shield and B+ battery cable, ensure there is
adequate clearance so it will no longer short out.
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3.
Inspect for any loose connections at the battery fuse block or for high resistance in the battery cables. Perform a loaded voltage drop test on the
negative battery cable, as well as the positive battery cable between the battery "+" post and the Battery Fuse Block, as shown below.
Note: When checking voltage drop, the voltage drop should be performed with the fuel injectors disabled and while cranking the engine. MIN/MAX on the Digital
Multi Meter (DMM) should NOT be used. The voltage drop should be monitored at a steady crank. The voltage drop should not exceed 200 mV. If the voltage
drop is above 200 mV, replace the affected cable(s). This test should be perform during a cold engine crank and also after a hot engine soak.
Warranty Information
The correction for this concern may be one of several repairs described above. For vehicles repaired under warranty, please use the appropriate warranty
labor operation based on the actual cause and repair.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the
remaining steps do not need to be performed.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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