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B14B7






B14B7 - Microphone 1 Circuit Open






For a complete wiring diagram, refer to.

When Monitored: With the ignition on.

Set Condition: The hands free module detects an open in the microphone circuit.






Test Step 1 - Check for Active DTC

Turn the ignition ON.

With the scan tool, record and erase DTCs.

Turn the ignition OFF, wait 30 seconds then turn the ignition ON.

With the scan tool, read DTCs.

Is the DTC active?

Yes

Go to Test Step 2.

No

The condition that caused this code to set is not present at this time. Check for an intermittent condition by inspecting the related wiring harness for chaffed, pierced, pinched, and partially broken wires. Also inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 2 - Inside Rearview Mirror






Turn the ignition OFF.

Disconnect the rearview mirror harness connector.

Connect a jumper wire from the microphone 1 in (+) circuit to ground.

Turn the ignition ON.

With the scan tool, read the active DTC's.

Does the scan tool display this DTC as active?

Yes

Go to Test Step 3.

No

Replace the rearview mirror.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 3 - Microphone 1 in (+) Circuit Open






Turn the ignition OFF.

Disconnect the radio C1 harness connector.

Disconnect the Inside rearview mirror harness connector.

Measure the resistance of the microphone 1in (+) circuit between the radio C1 connector and the inside rearview mirror connector.

Is the resistance less than 5.0 ohms?

Yes

Replace the hands free module.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Repair the microphone 1 in (+) circuit for an open.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior