Diagnostic Test

CHECK FOR AN ACTIVE DTC
NOTE:
If any Brake Switch DTCs are present in the PCM, diagnose those DTCs before continuing.

NOTE:
Verify the Stop Lamp Switch is properly adjusted before continuing.
1. Turn the ignition on.
2. With the scan tool, read DTCs.
  Does the scan tool display this DTC as active?
  
  Yes
  - Go To 2
  No
  - Test complete. The condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
CHECK CENTER HIGH MOUNTED STOP LAMP (CHMSL) OPERATION
1. Turn the ignition on.
2. Press the brake pedal.
  Does the CHMSL illuminate?
  
  Yes
  - Go To 5
  No
  - Go To 3
CHECK THE (A924) FUSED B (+) CIRCUIT FOR AN OPEN OR SHORT TO GROUND
1. Back probe and measure the voltage of the (A924) Fused B (+) circuit at the Stop Lamp Switch harness connector.
  Is the voltage above 10.0 volts?
  
  Yes
  - Go To 4
  No
  - Repair the (A924) Fused B (+) circuit for an open or short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
CHECK THE OPERATION OF THE STOP LAMP SWITCH
1. With the Brake Pedal pressed, back probe and measure the voltage of the (L53) Brake Lamp Control Output circuit at the Stop Lamp Switch harness connector.
  Is the voltage above 10.0 volts?
  
  Yes
  - Go To 5
  No
  - Replace the Stop Lamp Switch in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
CHECK THE (L53) BRAKE LAMP CONTROL OUTPUT CIRCUIT FOR VOLTAGE WITH THE STOP LAMP SWITCH DEPRESSED
1. Disconnect the TIPM C3 harness connector.
2. With the brake pedal pressed, check the voltage of the (L53) Brake Lamp Control Output circuit at the TIPM C3 harness connector.
  Is the voltage above 10.0 volts?
  
  Yes
  - Replace the Totally Integrated Power Module (TIPM) in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .
  No
  - Repair the (L53) Brake Lamp Control Output circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST .