Pinpoint Test N: The Circuit Deactivation Ignition Module (CDIM) Does Not Communicate With the Scan Tool

Communications Network

Pinpoint Test N: The Circuit Deactivation Ignition Module (CDIM) Does Not Communicate With the Scan Tool

Normal Operation

The Circuit Deactivation Ignition Module (CDIM) 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

- CDIM (Circuit Deactivation Ignition Module)

PINPOINT TEST N : THE CDIM (Circuit Deactivation Ignition Module) DOES NOT COMMUNICATE WITH 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.

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

N1 CHECK THE CDIM (Circuit Deactivation Ignition Module) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

- Ignition OFF.

- Disconnect: CDIM (Circuit Deactivation Ignition Module) C2500.

- Ignition ON.

- Measure the voltage between the CDIM (Circuit Deactivation Ignition Module) C2500-7, circuit CDC34 (WH/OG), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to N2.

No
VERIFY the Body Control Module (BCM) fuse 28 (15A) 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

N2 CHECK THE CDIM (Circuit Deactivation Ignition Module) GROUND CIRCUIT FOR AN OPEN

- Ignition OFF.

- Disconnect: Negative Battery Cable.

- Measure the resistance between the CDIM (Circuit Deactivation Ignition Module) C2500-11, circuit GD184 (BK/GY or BK/YE), harness side and ground.





Are the resistances less than 5 ohms?

Yes
GO to N3.

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

N3 CHECK THE MS-CAN (Medium Speed Controller Area Network) CIRCUITS BETWEEN THE CDIM (Circuit Deactivation Ignition Module) AND THE DLC (Data Link Connector) FOR AN OPEN

- Ignition OFF.

- Measure the resistance between the CDIM (Circuit Deactivation Ignition Module) C2500-5, circuit VDB06 (GY/OG), harness side and the Data Link Connector (DLC) C251-3, circuit VDB06 (GY/OG), harness side.





- Measure the resistance between the CDIM (Circuit Deactivation Ignition Module) C2500-12, 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 N4.

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

N4 CHECK FOR CORRECT CDIM (Circuit Deactivation Ignition Module) OPERATION

- Disconnect the CDIM (Circuit Deactivation Ignition Module) connector.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect the CDIM (Circuit Deactivation Ignition 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 CDIM (Circuit Deactivation Ignition Module). CLEAR the DTCs. REPEAT the network test with the scan tool. 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.