Pinpoint Test AA: The RETM (Rear Entertainment Module) Does Not Respond To The Scan Tool

Communications Network

Pinpoint Test AA: The RETM (Rear Entertainment Module) Does Not Respond To The Scan Tool

Normal Operation

The Rear Entertainment Module (RETM) communicates with the scan tool through the Medium Speed Controller Area Network (MS-CAN).

This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- RETM (Rear Entertainment Module)

PINPOINT TEST AA : THE RETM (Rear Entertainment Module) DOES NOT RESPOND TO THE SCAN TOOL

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

AA1 CHECK THE RETM (Rear Entertainment Module) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

- Ignition OFF.

- Disconnect: RETM (Rear Entertainment Module) C2949A.

- Ignition ON.

- Measure the voltage between the RETM (Rear Entertainment Module) C2949A-13, circuit SBP14 (BN/RD), harness side and ground.




Is the voltage greater than 10 volts?

Yes
GO to AA2.

No
VERIFY the Smart Junction Box (SJB) fuse 14 (10A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the network test with the scan tool. Electrical Diagrams

AA2 CHECK THE RETM (Rear Entertainment Module) GROUND CIRCUIT FOR AN OPEN

- Ignition OFF.

- Measure the resistance between the RETM (Rear Entertainment Module) C2949A-1, circuit GD114 (BK/BU), harness side and ground.




Is the resistance less than 5 ohms?

Yes
GO to AA3.

No
REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.

AA3 CHECK THE MS-CAN (Medium Speed Controller Area Network) CIRCUITS BETWEEN THE RETM (Rear Entertainment Module) AND THE DLC (Data Link Connector) FOR AN OPEN

- Disconnect: RETM (Rear Entertainment Module) C2949B.

- Measure the resistance between the RETM (Rear Entertainment Module) C2949B-14, circuit VDB06 (GY/OG), harness side and the DLC (Data Link Connector) C251-3, circuit VDB06 (GY/OG), harness side.




- Measure the resistance between the RETM (Rear Entertainment Module) C2949B-15, circuit VDB07 (VT/OG), harness side and the DLC (Data Link Connector) C251-11, circuit VDB07 (VT/OG), harness side.




Are the resistances less than 5 ohms?

Yes
GO to AA4.

No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.

AA4 CHECK FOR CORRECT RETM (Rear Entertainment Module) OPERATION

- Disconnect the RETM (Rear Entertainment Module) connector.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect the RETM (Rear Entertainment Module) connector and make sure it seats correctly.

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

Is the concern still present?

Yes
INSTALL a new RETM (Rear Entertainment Module). CLEAR the DTCs. REPEAT the network test with the scan tool.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.