B1277 - Microphone 1 Input Signal Circuit
B1277 Possible Causes
- Faulty Radio Volume Compensator Interior Noise Microphone
- Radio Volume Compensator Interior Noise Microphone harness is open or shorted
- Radio Volume Compensator Interior Noise Microphone circuit poor electrical connection
- Faulty Audio Amplifier
How is the B1277 code repair?Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
What is the cost to diagnose the B1277 code
Labor: 1.0The cost to diagnose the B1277 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
- Engine Light ON (or Service Engine Soon Warning Light)
B1277 MeaningThe active noise cancellation system uses three microphones in the vehicle headliner: one above each front seating position, and one above the rear seat. The Audio Amplifier provides a bias voltage to each microphone (+) and (-) signal circuits for operation of the microphone. The microphones monitor the vehicle cabin for undesirable engine sounds. The Audio Amplifier uses the microphone inputs and an engine RPM signal to determine the frequency of the undesirable sound. The Audio Amplifier performs a self diagnostic of the microphone circuits 16 seconds after initial power up, then periodically every 400 milliseconds thereafter.
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Information for specific makes
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