Enabling Conditions

Parking brake must be set, transmission in Park (A/T) or Neutral (M/T) and clutch pedal released. Service brake, accelerator pedal and brakelights must be functional. To operate system with hazard flashers, hi-mount brakelight circuit must be complete and operational.

The following error codes are displayed from APCM only:

• AErr
  
  Indicates an internal APCM fault.
• CErr
  
  Indicates that one or both BUS circuits are open or shorted.
• CrSd
  
  Indicates a fault on BUS circuits or internal APCM fault.
• EErr
  
  Indicates an internal APCM fault.

Identify APCM error code and perform appropriate procedure or test step:

• If APCM is inoperative at all times, go to step  1).
• If APCM is inoperative with hazard flashers, go to step  7).
• If APCM error code CErr or CrSD is displayed, go to step  5).
• If APCM error code EErr or AErr is displayed, replace APCM.