Pinpoint Test D: DTC P1572:62
Starting System
Pinpoint Test D: DTC P1572:62
Refer to Wiring Diagram Set 20, Starting System for schematic and connector information Electrical Diagrams.
Normal Operation
The IPC (Instrument Panel Cluster) sends a MS-CAN (Medium Speed Controller Area Network) message to the PCM (Powertrain Control Module) concerning the brake switch status sensed by the RFA (Remote Function Actuator). If the MS-CAN (Medium Speed Controller Area Network) message input does not match the PCM (Powertrain Control Module) brake input message a DTC is set.
- DTC P1571:62 (Brake Switch: Signal Compare Failure)- sets when the brake switch input to the RFA (Remote Function Actuator) module indicates the brake pedal is pressed but the Medium Speed Controller Area Network (MS-CAN) message transmitted by the Instrument Panel Cluster (IPC) module indicates the brake pedal is not pressed.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Cruise Control Deactivator Switch
- RFA (Remote Function Actuator) module
PINPOINT TEST D : DTC P1571:62
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
D1 CHECK FOR COMMUNICATION WITH THE SCAN TOOL
- Refer to Inspection and Verification in Information Bus, and follow the procedure to establish a session with the vehicle Inspection and Verification.
Does the PCM pass the network test?
Yes
GO to D2.
No
REFER to Information Bus to diagnose no communication with the PCM.
D2 CHECK THE PCM MODULE BRAKE SWITCH (BOO) PID
- Enter the following diagnostic mode on the scan tool: DataLogger- PCM (Powertrain Control Module).
- While observing the BOO PID, apply the brake pedal.
Does the PID change from OFF to ON?
Yes
GO to D3.
No
REFER to Fire Suppression System, PPT B, to diagnose brake switch concern.
D3 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH FOR AN OPEN
- Ignition OFF.
- Disconnect: Cruise Control Deactivator Switch C278.
- Inspect both ends of the connector for damage, pushed-out pins, corrosion, loose wires and missing or damaged seals.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger- RFA (Remote Function Actuator) module.
- CONNECT and remove a fused jumper wire between the cruise control deactivator switch C278-2, circuit CCA29 (GN/BU), harness side and the cruise control deactivator switch C278-1, circuit GD187 (BK/GN), harness side, while monitoring the RFA (Remote Function Actuator) BRAKE_SW PID.
Does the PID status change?
Yes
INSTALL a new cruise control deactivator switch. TEST the system for normal operation.
No
GO to D4.
D4 CHECK THE CRUISE CONTROL DEACTIVATOR SWITCH GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure the resistance between cruise control deactivator switch C278-1, circuit GD187 (BK/GN) and ground.
Is the resistance less than 5 ohms?
Yes
GO to D5.
No
REPAIR circuit GD187 (BK/GN). TEST the system for normal operation.
D5 CHECK THE INPUT CIRCUIT TO THE RFA FOR AN OPEN
- Disconnect: RFA (Remote Function Actuator) C3503B.
- Inspect both ends of the connector for damage, pushed-out pins, corrosion, loose wires and missing or damaged seals.
- Measure the resistance between RFA (Remote Function Actuator) module C3503B-21, circuit CCA29 (GN/BU) harness side and cruise control deactivator switch C278-2, circuit CCA29 (GN/BU), harness side.
Is the resistance less than 0.5 ohm?
Yes
GO to D6.
No
REPAIR circuit CCA29 (GN/BU). TEST the system for normal operation.
D6 CHECK THE IPC (Instrument Panel Cluster) MODULE INPUT CIRCUIT FOR AN OPEN
- Disconnect: IPC (Instrument Panel Cluster) C220.
- Inspect both ends of the connector for damage, pushed-out pins, corrosion, loose wires and missing or damaged seals.
- Measure the resistance between IPC (Instrument Panel Cluster) module C220-29, circuit CCA29 (GN/BU) harness side and cruise control deactivator switch C278-2, circuit CCA29 (GN/BU), harness side.
Is the resistance less than 0.5 ohm?
Yes
GO to D7.
No
REPAIR circuit CCA29 (GN/BU). TEST the system for normal operation.
D7 CHECK FOR CORRECT RFA (Remote Function Actuator) MODULE OPERATION
- Disconnect all the RFA (Remote Function Actuator) module connectors.
- Inspect both ends of the connectors for damage, pushed-out pins, corrosion, loose wires and missing or damaged seals.
- Connect all the RFA (Remote Function Actuator) module connectors and make sure they seat correctly.
- Connect the IPC (Instrument Panel Cluster) module connector and make sure the connector seat correctly.
- Connect the cruise control deactivator switch connector and make sure the connector seat correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new RFA module. TEST the system for normal operation
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.