Cruise Control Inoperative - keywords abs B3894 brake cylinder ebcm inop master module pressure sensor switch trailer
| Subject: | Cruise Control Inoperative - keywords abs B3894 brake cylinder ebcm inop master module pressure sensor switch trailer |
| Models: | 2007-2008 Chevrolet Silverado |
| 2007-2008 GMC Sierra |
| With RPO JL1 |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some owners may comment of the cruise control being inoperative. The Trailer Brake Control Module (TBCM) may set a DTC B3894. If normal diagnostics do not lead to a correction, check the "Master Cylinder Pressure" sensor parameter listed in the TBCM data list. If it is displaying pressure with no brake pedal input, suspect a concern with the master cylinder pressure sensor, wiring/terminals, EBCM, ect. for HD models. On light duty models the master cylinder pressure sensor is internal to the BPMV/EBCM.
Recommendation/Instructions:
Diagnosis and repair as necessary.
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.
