Diagnostic Test
- DTC IS ACTIVE
- Turn the ignition on.
- With the scan tool, monitor the states of Brake Signal 1 and Brake Signal 2 while pressing and releasing the brake pedal several times.
Do the states change from Pressed when the pedal is pressed to Not Pressed when the pedal is released?
Yes
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure
No
- Go to step 2
- (B15) BRAKE SIGNAL 1 CIRCUIT
- Turn the ignition off.
- Disconnect the Powertrain Control Module (PCM) connector.
- Using a 12 volt test light connected to 12 volts, check the (B15) Brake Signal 1 circuit in the Powertrain Control Module (PCM) harness connector while pressing and releasing the brake pedal several times.
Does the test light change from illuminated when the pedal is pressed to not illuminated when the pedal is released?
Yes
- Go to step 3
No
- Go to step 4
- (B16) BRAKE SIGNAL 2 CIRCUIT
- Turn the ignition on.
- Using a 12 volt test light connected to ground, check the (B16) Brake Signal 2 circuit in the Powertrain Control Module (PCM) harness connector while pressing and releasing the brake pedal several times.
Does the test light change from illuminated when the pedal is pressed to not illuminated when the pedal is released?
Yes
- Go to step 11
No
- Go to step 7
- (Z908) GROUND CIRCUIT OPEN OR HIGH RESISTANCE
- Turn the ignition off.
- Disconnect the Stop Lamp Switch connector.
- Using a 12 volt test light connected to 12 volts, check the (Z908) Ground circuit in the Stop Lamp Switch harness connector.NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Is the test light illuminated and bright?
Yes
- Go to step 5
No
- Repair the (Z908) Ground circuit for an open circuit or high resistance.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- (B15) BRAKE SIGNAL 1 CIRCUIT SHORTED TO GROUND
- Measure the resistance between ground and the (B15) Brake Signal 1 circuit in the Stop Lamp Switch harness connector.
Is the resistance above 100 ohms?
Yes
- Go to step 6
No
- Repair the (B15) Brake Signal 1 circuit for a short to ground.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- Measure the resistance between ground and the (B15) Brake Signal 1 circuit in the Stop Lamp Switch harness connector.
- (B15) BRAKE SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE
NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.
- Measure the resistance of the (B15) Brake Signal 1 circuit between the Stop Lamp Switch harness connector and the Powertrain Control Module (PCM) harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go to step 10
No
- Repair the (B15) Brake Signal 1 circuit for an open circuit or high resistance.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- Measure the resistance of the (B15) Brake Signal 1 circuit between the Stop Lamp Switch harness connector and the Powertrain Control Module (PCM) harness connector.
- (F202) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT OPEN OR HIGH RESISTANCE
- Turn the ignition off.
- Disconnect the Stop Lamp Switch connector.
- Turn the ignition on.
- Using a 12 volt test light connected to ground, check the (F202) Fused Ignition Switch Output (Run-Start) circuit in the Stop Lamp Switch harness connector.NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Is the test light illuminated and bright?
Yes
- Go to step 8
No
- Repair the (F202) Fused Ignition Switch Output (Run-Start) circuit for an open circuit or high resistance.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- (B16) BRAKE SIGNAL 2 CIRCUIT SHORTED TO VOLTAGE
- Measure the voltage of the (B16) Brake Signal 2 circuit in the Stop Lamp Switch harness connector.
Is there any voltage present?
Yes
- Repair the (B16) Brake Signal 2 circuit for a short to voltage.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Go to step 9
- Measure the voltage of the (B16) Brake Signal 2 circuit in the Stop Lamp Switch harness connector.
- (B16) BRAKE SIGNAL 2 CIRCUIT OPEN OR HIGH RESISTANCE
NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.
- Measure the resistance of the (B16) Brake Signal 2 circuit between the Stop Lamp Switch harness connector and the Powertrain Control Module (PCM) harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go to step 10
No
- Repair the (B16) Brake Signal 2 circuit for an open circuit or high resistance.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- Measure the resistance of the (B16) Brake Signal 2 circuit between the Stop Lamp Switch harness connector and the Powertrain Control Module (PCM) harness connector.
- STOP LAMP SWITCH
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Stop Lamp Switch and the Powertrain Control Module (PCM).
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals.
- Refer to any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Replace the Stop Lamp Switch in accordance with the Service Information.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- POWERTRAIN CONTROL MODULE (PCM)
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Stop Lamp Switch and the Powertrain Control Module (PCM).
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals.
- Refer to any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.
- Perform the PCM Verification Test. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .