B143A

B143A- MICROPHONE 1 CIRCUIT PERFORMANCE







- When Monitored:
With the ignition on.

- Set Condition:
The Radio detects a fault in any of the microphone circuits.





1. CHECK FOR ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, read the active DTCs.

Does the scan tool display B143A- MICROPHONE 1 CIRCUIT PERFORMANCE 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 HANDS FREE MICROPHONE
1. Turn the ignition off.
2. Disconnect the Hands Free Microphone harness connector.
3. Turn the ignition on.
4. With the scan tool, read the active DTCs.

Does the scan tool display B143A- MICROPHONE 1 CIRCUIT PERFORMANCE as active?

Yes

- Go To 3

No

- Replace the Hands Free Microphone. Microphone - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. CHECK THE (X712) MICROPHONE 1 IN (+) AND (X792) MICROPHONE IN (-) CIRCUITS FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Disconnect the Radio C1 harness connector.
3. Measure the resistance between ground and the (X712) Microphone 1 IN (+) circuit.
4. Measure the resistance between ground and the (X792) Microphone IN (-) circuit.

Is the resistance below 10K Ohms?

Yes

- Repair the (X712) Microphone 1 IN circuit or the (X792) Microphone IN (-) circuit for short to ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 4

4. CHECK THE (X712) MICROPHONE 1 IN (+) AND THE (X792) MICROPHONE IN (-) CIRCUITS FOR A SHORT TO VOLTAGE




1. Turn the ignition on.
2. Measure the voltage between ground and the (X712) Microphone 1 IN (+) circuit.
3. Measure the voltage between ground and the (X792) Microphone 1 IN (-) circuit.

Is the voltage above 1.0 volt?

Yes

- Repair the (X712) Microphone 1 IN (+) circuit or the (X792) Microphone 1 IN (-) circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. CHECK THE (X712) MICROPHONE 1 IN (+) CIRCUIT FOR AN OPEN




1. Turn the ignition off.
2. Measure the resistance of the (X712) Microphone 1 IN (+) circuit.

Is the resistance below 5.0 Ohms?

Yes

- Go To 6

No

- Repair the (X712) Microphone 1 IN (+) or the (X792) Microphone IN (-) circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

6. CHECK THE (X792) MICROPHONE 1 IN (-) CIRCUIT FOR AN OPEN




1. Measure the resistance of the (X792) Microphone IN (-) circuit.

Is the resistance below 5.0 Ohms?

Yes

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

No

- Repair the (X792) Microphone IN (-) circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.