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Brake Light Switch Inoperative, Brake Warning Buzzer Sounding and Brake Warning Light On, DTCs C0164, C0272 Set (Remove and Splice Wire/Remove CHMSL Fuse/Replace Stop Lamp Switch)

Subject:Brake Light Switch Inoperative, Brake Warning Buzzer Sounding and Brake Warning Light On, DTCs C0164, C0272 Set (Remove and Splice Wire/Remove CHMSL Fuse/Replace Stop Lamp Switch)

Models:2004-2006 Chevrolet Kodiak C4500-C8500 Series
2004-2006 GMC TopKick C4500-C8500 Series
2005-2006 Isuzu HTR, HVR, HXR Conventional Models



Condition

Some customers may comment that the brake light switch has become inoperative after extended usage. They may also comment that the audible brake warning buzzer is sounding and that the brake warning lamp is illuminated. Upon investigation, the technician may find DTCs C0164 and/or C0272 set.

Cause

Current flow through the stop lamp switch contacts is insufficient to allow the contacts to operate cleanly.

Correction

Increase current flow through the switch contacts by relocating a wire from the instrument panel (IP) harness using the procedure below.


    Object Number: 1867970  Size: MF
  1. Access the RH IP fuse block (1).
  2. Drop the IP fuse block for access to the back of the fuse block.

  3. Object Number: 1867971  Size: MF

    Object Number: 1867973  Size: MF
  4. Remove CKT 1740, orange wire, from cavity E7 in the IP distribution center.

  5. Object Number: 1867975  Size: MF
  6. Splice the orange wire, CKT 1740, to the wire in cavity S7 in the IP relay center at the location shown in the above schematic. Refer to Wiring Systems in SI for splicing information.
  7. Remove and discard the 20A CHMSL fuse.
  8. Replace the stop lamp switch with P/N 25771554. Refer to Stop Lamp Switch Replacement in SI.

Parts Information

Part Number

Description

Qty

25771554

Switch, S/Lp

1

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

H9722*

Brake Stop Lamp Switch Rewire and Switch Replacement

0.7 hr

*This is a unique labor operation number for bulletin use only. The number will not be published in the Labor Time Guide.