NHTSA ID Number: 10126992
Manufacturer Communication Number: PIT5529A
TSB/Document Date: 2018-01-16
Summary
This Preliminary Information communication provides information to the technician about vehicles that have Trailer connection not recognized or “Check Trailer wiring” or “Service Trailer Brake” message. Technician may find Diagnostic Trouble Codes C1112, C1113, C1114, C111B, U1556, and/or U1505. Technician will need to inspect the battery and Trailer Brake Power Module connector for corroded terminals and replace as necessary.
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TSB/Document ID: PIT5529A
Replacement Service Bulletin Number:
MFR Communication Date: 2017-12-21
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
Bulletin No.: PIT5529A
Published date: 12/22/2017
Preliminary Information
PIT5529A Service Trailer Brake Message With DTC's C1112 C1113 C1114 C111B U1556 and/or U1505
Models
Brand:
Model:
Model Years:
VIN:
from
Engine:
to
Transmissions:
Silverado 1500
2014
All
All
All
All
Silverado
2015 - 2018
All
All
All
All
Suburban
2015 - 2018
All
All
All
All
Tahoe
2015 - 2018
All
All
All
All
Sierra 1500
2014
All
All
All
All
Sierra
2015 - 2018
All
All
All
All
Yukon
2015 - 2018
All
All
All
All
Involved Region or Country:
North America
Additional RPO/s:
JL1
Some customers may comment on any of the following Trailer Brake Issues
Condition:
Trailer Connection not recognized
Check Trailer Wiring message
Service Trailer Brake Message with any of the following DTC's C1112 C1113 C1114 C111B U1556 and/or
U1505
These concerns could be caused by either of the following concerns:
Concern 1
These concerns could be caused by low battery voltage due to a battery issue.
Concern 2
These concerns could be caused by water/dirt/etc. getting into the Trailer Brake Power Module (K133) connector
from a missing cavity plug. Connector hydro-locking can cause pressure to build up as the connector is
plugged in and push the cavity plug out. Shown below is the Trailer Brake Power Module and its connector
cavity plug which is partially pushed out and not fully seated.
Cause:
Correction:
Correction 1
Before any in depth diagnostics are performed, the battery state of health should be checked using the EL-50313 Midtronics® GR8 Battery
Charger/Tester. Address any battery issues first before continuing with normal diagnostics.
Correction 2
Inspect the Trailer Brake Power Module/Connector for corroded terminals and replace as necessary. Make sure all connector cavity plugs are
installed and fully seated into the connector body, shown below (1). Pay close attention to the cavity plugs after plugging the trailer brake power
module connector back onto the module to make sure the cavity plugs have stayed seated and not pushed out.
Warranty Information
For wiring repairs covered under warranty, please refer to latest version of bulletin 10-00-89-005 for warranty information on wire/connector
repairs.
Version History
Version
2
Modified
12-21-17 Updated to combine with PIT5521A and add 2018 model year.
© 2016 General Motors
. All Rights Reserved.
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