P0572
P0572-BRAKE SWITCH 1 STUCK ON
For a complete wiring diagram Refer to the Wiring Information.
- When Monitored:
When vehicle speed cycles from 0 kph to 48 kph (30 mph) at least 10 times.
- Set Condition:
When the PCM recognizes Brake Switch No.1 is mechanically stuck in the low/on position. Two Trip Fault. Three Global Good Trips to Clear.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. ACTIVE DTC
NOTE: Verify battery voltage is greater than 10 volts.
1. Start the engine.
2. Allow the engine to reach normal operating temperature.
3. With a scan tool, select View DTCs.
NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.
Is the DTC Active or Pending at this time?
Yes
- Go To 2
No
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition Test.
2. STOP LAMP SWITCH
1. Turn the ignition off.
2. Remove the Stop Lamp Switch and disconnect the harness connector.
3. Measure the resistance between the (Z940) Ground circuit terminal and the (B15) Brake Switch No.1 Signal terminal in the Stop Lamp Switch.
4. Measure the resistance between the (F942) Fused Ignition Switch Output circuit terminal and the (B16) Brake Switch No.2 Signal circuit terminal in the Stop Lamp Switch.
5. Apply and release the Stop Lamp Switch plunger while monitoring the ohmmeter.
Does the resistance change from below 5.0 ohms to an open circuit?
Yes
- Go To 3
No
- Verify that there is good pin to terminal contact in the Switch and Powertrain Control Module connectors. If OK, replace the Stop Lamp Switch.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
3. (B15) BRAKE SWITCH NO.1 SIGNAL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the C3 PCM harness connector.
3. Measure the resistance between ground and the (B15) Brake Switch No.1 Signal circuit in the Stop Lamp Switch harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short to ground in the (B15) Brake Switch No.1 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 4
4. (B16) BRAKE SWITCH NO.2 SIGNAL CIRCUIT OPEN
CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install PCM Pinout Box 8815 to perform diagnosis.
1. Measure the resistance of the (B16) Brake Switch No.2 Signal circuit from the Stop Lamp Switch harness connector to the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?
Yes
- Go To 5
No
- Repair the open in the (B16) Brake Switch No.2 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
5. 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 connectors.
4. Search for any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.