Pinpoint Test R: The Accessory Protocol Interface Module (APIM) Does Not Respond To The Scan Tool

Communications Network

Pinpoint Test R: The Accessory Protocol Interface Module (APIM) Does Not Respond To The Scan Tool


Normal Operation

The Accessory Protocol Interface Module (APIM) communicates with the scan tool through the High Speed Controller Area Network (HS-CAN).

This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- APIM (Accessory Protocol Interface Module)

PINPOINT TEST R : THE APIM (Accessory Protocol Interface Module) DOES NOT RESPOND TO THE SCAN TOOL

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings.

R1 CHECK THE APIM (Accessory Protocol Interface Module) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

- Disconnect: APIM (Accessory Protocol Interface Module) C2298.

- Ignition ON.

- Measure the voltage between the APIM (Accessory Protocol Interface Module) C2298-1, circuit SBP29 (GY/RD), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to R2.

No
VERIFY the Body Control Module (BCM) fuse 29 (20A) is OK. If OK, REPAIR the circuit. 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. [1][2]Diagrams By Number

R2 CHECK THE APIM (Accessory Protocol Interface Module) GROUND CIRCUIT FOR AN OPEN

- Ignition OFF.

- Disconnect: Negative Battery Cable.

- Measure the resistance between the APIM (Accessory Protocol Interface Module) C2298-37, circuit GD114 (BK/BU or BK), harness side and ground; and between the APIM (Accessory Protocol Interface Module) C2298-38, circuit GD114 (BK/BU or BK), harness side and ground.





Are the resistances less than 5 ohms?

Yes
GO to R3.

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

R3 CHECK THE HS-CAN (High Speed Controller Area Network) CIRCUITS BETWEEN THE APIM (Accessory Protocol Interface Module) AND THE DLC (Data Link Connector) FOR AN OPEN

- Measure the resistance between the APIM (Accessory Protocol Interface Module) C2298-53, circuit VDB04 (WH/BU), harness side and the Data Link Connector (DLC) C251-6, circuit VDB04 (WH/BU), harness side.





- Measure the resistance between the APIM (Accessory Protocol Interface Module) C2298-54, circuit VDB05 (WH), harness side and the DLC (Data Link Connector) C251-14, circuit VDB05 (WH), harness side.





Are the resistances less than 5 ohms?

Yes
GO to R4.

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

R4 CHECK THE MS-CAN (Medium Speed Controller Area Network) CIRCUITS BETWEEN APIM (Accessory Protocol Interface Module) AND THE DLC (Data Link Connector) FOR AN OPEN

- Measure the resistance between the APIM (Accessory Protocol Interface Module) C2298-16, 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 APIM (Accessory Protocol Interface Module) C2298-17, 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
CONNECT the negative battery cable. GO to R5.

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

R5 CHECK FOR CORRECT APIM (Accessory Protocol Interface Module) OPERATION

- Disconnect all the APIM (Accessory Protocol Interface Module) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the APIM (Accessory Protocol Interface 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 APIM (Accessory Protocol Interface 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.