Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

ACTIVE DTC
NOTE:
Make sure the Stop Lamp Switch is adjusted properly before continuing.
1. Ignition on, engine not running.
2. With the scan tool, select View DTCs.
3. It may be necessary to press and release the Brake Pedal to get the code to become Active.
  Is the DTC Active at this time?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
STOP LAMP SWITCH OPERATION
1. Turn the ignition off.
2. Disconnect the Stop Lamp Switch harness connectors.
3. Measure the resistance between the Brake Lamp Switch Output circuit terminal and the Fused B+ circuit terminal in the Stop Lamp Switch.
4. Apply and release the Stop Lamp Switch while monitoring the Ohmmeter.
  Does the resistance change from below 5.0 Ohms to an open circuit when pressing and releasing the brake switch?
  
  Yes
  - Go To 3
  No
  - Replace the Stop Lamp Switch.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
STOP LAMP SWITCH OPERATION
1. Measure the resistance between the Fused Ignition Run-Start Control Output circuit terminal and the Brake Signal 2 circuit terminal in the Stop Lamp Switch.
2. Apply and release the Stop Lamp Switch while monitoring the Ohmmeter.
  Does the resistance change from below 5.0 Ohms to an open circuit when pressing and releasing the Stop Lamp switch?
  
  Yes
  - Go To 4
  No
  - Replace the Stop Lamp Switch.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
CHECK THE (B134) BRAKE SIGNAL 2 CIRCUIT FOR A SHORT TO VOLTAGE
1. Disconnect the BCM C1 harness connector.
2. Ignition on, engine not running.
3. Measure the voltage on the (B134) Brake Signal 2 circuit in the Stop Lamp Switch harness connector.
  Is there any voltage present?
  
  Yes
  - Repair the short to voltage in the (B134) Brake Signal 2 circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Go To 5
CHECK THE (L56) BRAKE LAMP SWITCH OUTPUT CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Measure the resistance between ground and the (L56) Brake Lamp Switch Output circuit in the Stop Lamp Switch harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 6
  No
  - Repair the short to ground in the (L56) Brake Lamp Switch Output circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Stop Lamp Switch and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Switch and Powertrain Control Module harness connectors.
4. Perform any Technical Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .