B143D-1A

B143D-1A -MICROPHONE 2-CIRCUIT RESISTANCE BELOW THRESHOLD

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





Theory of Operation

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

- When Monitored:
With the ignition on.

- Set Condition:
The Radio detects the Microphone 2 IN (+) circuit is shorted to the Microphone 2 IN (-) circuit for greater than 10 seconds.





Diagnostic Test

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-1A -MICROPHONE 2-CIRCUIT RESISTANCE BELOW THRESHOLD 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. Turn the ignition on.
4. With the scan tool, read the active DTCs.

NOTE: B143D-13-MICROPHONE 2 - CIRCUIT OPEN should display as active as a result of this test.

Does the scan tool display: B143D-1A -MICROPHONE 2-CIRCUIT RESISTANCE BELOW THRESHOLD 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 (+) AND THE (X723) MICROPHONE 2 IN (-) CIRCUITS FOR A SHORT TOGETHER
1. Turn the ignition off.
2. Disconnect the Radio harness connector.
3. Measure the resistance between the (X722) Microphone 2 IN (+) circuit, and the (X723) Microphone 2 IN (-) circuit.

Is the resistance below 10K Ohms?

Yes

- Repair the (X722) Microphone 2 IN (+) and the (X723) Microphone 2 IN (-) circuits for a short together.
- Perform the BODY VERIFICATION TEST. Body Verification Test .

No

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