Antitheft and Alarm Systems

Anti-Theft - With Intelligent Access (IA)

Pinpoint Test H: DTC U201F:31

Normal Operation

When the Intelligent Access (IA) key is activated by one of the low frequency passive start antennas, the transmitter in the IA (Intelligent Access) key sends a radio signal to the Tire Pressure Monitor (TPM) module. The TPM (Tire Pressure Monitor) module then communicates the command to the Remote Function Actuator (RFA) module, and the RFA (Remote Function Actuator) either switches the ignition to the requested mode or starts the engine.

The TPM (Tire Pressure Monitor) module receives voltage at all times and has a dedicated ground circuit. The TPM (Tire Pressure Monitor) module sends Tire Pressure Monitoring System (TPMS) information over the Medium Speed Controller Area Network (MS-CAN) to the Body Control Module (BCM). The TPM (Tire Pressure Monitor) module sends all Remote Keyless Entry (RKE) and IA (Intelligent Access) key information and requests to the RFA (Remote Function Actuator) module through a dedicated single circuit network.

In the event of a failure with the TPM (Tire Pressure Monitor) module, the vehicle experiences a no-start unless the IA (Intelligent Access) key is placed in the backup slot.

- DTC U201F:31 (External Receiver: No Signal)- an on-demand DTC that sets when the RFA (Remote Function Actuator) module has lost communication with the TPM (Tire Pressure Monitor) module.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- TPM (Tire Pressure Monitor) module

- RFA (Remote Function Actuator) module

PINPOINT TEST H : DTC U201F:31

H1 CHECK FOR COMMUNICATION WITH THE TPM (Tire Pressure Monitor) MODULE

- Enter the following diagnostic mode on the scan tool: Network Test.

Does the TPM (Tire Pressure Monitor) module pass the network test?

Yes
GO to H2.

No
REFER to Information Bus.

H2 CHECK THE TPM (Tire Pressure Monitor) MODULE COMMUNICATION CIRCUIT FOR A SHORT TO VOLTAGE

NOTE: Place the IA (Intelligent Access) key in the backup slot for this pinpoint test.

- Ignition OFF.

- Disconnect: TPM (Tire Pressure Monitor) Module C4321.

- Disconnect: RFA (Remote Function Actuator) Module C2153E.

- Ignition ON.

- Measure the voltage between the TPM (Tire Pressure Monitor) module C4321-3, circuit VPL56 (BU/GY), harness side and ground.






Is any voltage present?

Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

No
GO to H3.

H3 CHECK THE TPM (Tire Pressure Monitor) MODULE COMMUNICATION CIRCUIT FOR AN OPEN OR SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the TPM (Tire Pressure Monitor) module C4321-3, circuit VPL56 (BU/GY), harness side and the RFA (Remote Function Actuator) module C2153E-1, circuit VPL56 (BU/GY), harness side; and between the TPM (Tire Pressure Monitor) module C4321-3, circuit VPL56 (BU/GY), harness side and ground.






Is the resistance less than 5 ohms between the TPM (Tire Pressure Monitor) module and the RFA (Remote Function Actuator) module; and greater than 10,000 ohms between the TPM (Tire Pressure Monitor) module and ground?

Yes
INSTALL a new TPM (Tire Pressure Monitor) module. CLEAR the DTCs. REPEAT the self-test. If the concern is still present, GO to H4.

No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

H4 CHECK FOR CORRECT RFA (Remote Function Actuator) MODULE OPERATION

- Disconnect all the RFA (Remote Function Actuator) module connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the RFA (Remote Function Actuator) module connectors and make sure they seat correctly.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new RFA (Remote Function Actuator) 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.