Telematics Gateway Module (TGM)

B143D-13-MICROPHONE 2 - CIRCUIT OPEN

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Telematics Gateway (TGW) controls and monitors both the (X722) microphone 2 input circuit (+) and the (X723) microphone 2 input circuit (-) for a concern. The TGW communicates over the CAN-AT Bus and the CAN-Interior Bus. The microphone is located in the rearview mirror.

- When Monitored:
With the ignition on.

- Set Condition:
The TGW detects an open on either the (X722) Microphone 2 IN (+) circuit or the (X723) Microphone 2 IN (-) circuit for greater than 10 seconds.





1. CHECK FOR AN ACTIVE DTC

NOTE: Verify the connection of the Rearview Mirror harness connector.

1. Turn the ignition on.
2. With the scan tool, read the active DTCs.

Does the scan tool display: B143D-13-MICROPHONE 2 - CIRCUIT OPEN as active?

Yes

- Go To 2

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK THE INSIDE REARVIEW MIRROR
1. Turn the ignition off.
2. Disconnect the Inside Rearview Mirror harness connector
3. Connect a jumper wire between the (X722) Microphone 2 IN (+) and the (X723) Microphone 2 IN (-) circuits.
4. Turn the ignition on.
5. With the scan tool, read the DTCs.

NOTE: B143D-2B-MICROPHONE 2 - WIRES SHORTED TOGETHER should display as active as a result of this test.

Does the scan tool display: B143D-13-MICROPHONE 2 - CIRCUIT OPEN as active?

Yes

- Go To 3

No

- Replace the Inside Rearview Mirror.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. CHECK THE (X722) MICROPHONE 2 IN (+) CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the TGW harness connector.
3. Measure the resistance of the (X722) Microphone 2 IN (+) circuit between the Inside Rearview Mirror and TGW harness connectors.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (X722) Microphone 2 IN (+) circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 4

4. CHECK THE (X723) MICROPHONE 2 IN (-) CIRCUIT FOR AN OPEN
1. Measure the resistance of the (X723) Microphone 2 IN (-) circuit between the Inside Rearview Mirror and TGW harness connectors.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (X723) Microphone 2 IN (-) circuit for an open.
- Perform the BODY VERIFICATION TEST.Body Verification Test.

No

- Replace the TGW.
- Perform the BODY VERIFICATION TEST. Body Verification Test.