LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2015 >> Regal GS, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Cruise Control Systems >> Diagnostic Information and Procedures >> DTC B3794, P0564, P0565, P0567, P0568, P056C, P0580, P0581, P155A-P155C, or P162C: Cruise Control Malfunction >> Circuit/System Testing

Circuit/System Testing

NOTE:
  • An open ignition circuit or fuse before the control module will cause communication DTCs or power mode mismatch DTCs to set against or in the control module. This failure mode will be diagnosed in the no communications diagnostic procedure or power mode mismatch.
  • This test assumes the ignition circuit has a module driver that will open under a high current condition before the fuse opens.
  • The module driver can open under normal conditions such as battery run down protection or a retained accessory power mode.
  1. Ignition OFF, disconnect the harness connector at the S70L Steering Wheel Controls Switch-Left, ignition ON.
  2. Verify a test lamp illuminates between the ignition circuit terminal 10 and ground.
    • If the test lamp does not illuminate 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
    2. Test for greater than 100Ω between the ignition circuit and ground.
      • If 100Ω or less, repair the short to ground on the circuit.
      • If greater than 100Ω
    3. Test for less than 2Ω in the ignition circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, test or replace the K9 Body Control Module.
    • If the test lamp illuminates 
  3. Verify the scan tool BCM Cruise Control Switch Status parameter is Open/High Resistance.
    • If not Open/High Resistance 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON.
    2. Test for less than 1V between the signal circuit terminal 9 and ground.
      • If 1V or greater, repair the short to voltage on the circuit.
      • If less than 1V, replace the K9 Body Control Module.
    • If Open/High Resistance 
  4. Install a 3A fused jumper wire between the signal circuit terminal 9 and the ignition circuit terminal 10.
  5. Verify the scan tool BCM Cruise Control Switch Status parameter is Short to Battery.
    • If not Short to Battery 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the signal circuit terminal 9 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2Ω in the signal circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K9 Body Control Module.
    • If Short to Battery 
  6. Test or replace the S70L Steering Wheel Controls Switch-Left.
scientia non olet · About LEMON Manuals