P0703
P0703-BRAKE SWITCH 2 PERFORMANCE
For a complete wiring diagram, refer to the Wiring Information.
- When Monitored:
With the gear selector in drive, vehicle speed above a minimum value, and battery voltage greater than 10.4 volts.
- Set Condition:
The PCM detects that the actual state of Brake Signal 1 or Brake Signal 2 does not match the desired state during monitoring. One trip fault.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. PCM Pre-Diagnostic Troubleshooting Procedure
Diagnostic Test
1. DTC IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, monitor the Brake Signal 1 and Brake Signal 2 states while pressing and releasing the brake pedal several times.
Do the Brake Signal states change appropriately as the pedal is pressed and released?
Yes
- Perform the INTERMITTENT CONDITION diagnostic procedure. PCM Intermittent Condition Test.
No
- Go To 2
2. (B15) BRAKE SIGNAL 1 CIRCUIT
1. Turn the ignition off.
2. Disconnect the Stop Lamp Switch harness connector.
3. Using a 12-volt test light connected to 12 volts, check the (B15) Brake Signal 1 circuit at the Stop Lamp Switch harness connector while pressing and releasing the brake pedal several times.
Does the test light change from illuminated to not illuminated as the brake pedal is pressed and released?
Yes
- Go To 3
No
- Go To 4
3. (B16) BRAKE SIGNAL 2 CIRCUIT
1. Turn the ignition on.
2. Using a 12-volt test light connected to ground, check the (B16) Brake Signal 2 circuit at the Stop Lamp Switch harness connector while pressing and releasing the brake pedal several times.
Does the test light change from illuminated to not illuminated as the brake pedal is pressed and released?
Yes
- Go To 11
No
- Go To 7
4. (Z912) GROUND CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Stop Lamp Switch connector.
3. Using a 12-volt test light connected to 12 volts, check the (Z912) 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 5
No
- Repair the open or high resistance in the (Z912) Ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
5. (B15) BRAKE SIGNAL 1 CIRCUIT SHORTED TO GROUND
1. 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 6
No
- Repair the short to ground in the (B15) Brake Signal 1 circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
6. (B15) BRAKE SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Powertrain Control Module (PCM) C1 harness connector.
3. Measure the resistance of the (B15) Brake Signal 1 circuit between the Stop Lamp Switch harness connector and the PCM C1 harness connector
Is the resistance below 5.0 Ohms?
Yes
- Go To 10
No
- Repair the open or high resistance in the (B15) Brake Signal 1 circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
7. (F202) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Stop Lamp Switch connector.
3. Turn the ignition on.
4. 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 8
No
- Repair the open or high resistance in the (F202) Fused Ignition Switch Output (Run-Start) circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
8. (B16) BRAKE SIGNAL 2 CIRCUIT SHORTED TO VOLTAGE
1. 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 short to voltage in the (B16) Brake Signal 2 circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 9
9. (B16) BRAKE SIGNAL 2 CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Powertrain Control Module (PCM) C1 harness connector.
3. Measure the resistance of the (B16) Brake Signal 2 circuit between the Stop Lamp Switch harness connector and the PCM C1 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 10
No
- Repair the open or high resistance in the (B16) Brake Signal 2 circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
10. STOP LAMP SWITCH
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.
4. Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace the Stop Lamp Switch.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
11. 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.
4. Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module (PCM). Powertrain Control Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.