B1277 Code - Microphone 1 Input Signal Circuit
Quick Answer
For Cellular, Entertainment, and Navigation Systems: The Human Machine Interface Control Module uses the cellular telephone microphone for voice recognition and cellular features. Common causes include Faulty Cellular Phone Microphone (For Cellular, Entertainment, and Navigation Systems), Faulty Radio Volume Compensator Interior Noise Microphone (For Active Noise Cancellation System), Faulty Audio Amplifier (For Active Noise Cancellation System). Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
- What it means
- B1277 indicates Microphone 1 Input Signal Circuit.
- Common causes
- Common causes include Faulty Cellular Phone Microphone (For Cellular, Entertainment, and Navigation Systems), Faulty Radio Volume Compensator Interior Noise Microphone (For Active Noise Cancellation System), Faulty Audio Amplifier (For Active Noise Cancellation System).
- Severity
- Low - monitor the vehicle and repair when practical.
- Can I drive?
- The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.
Code B1277 Description
The Human Machine Interface Control Module uses the cellular telephone microphone for voice recognition and cellular features. The Human Machine Interface Control Module provides a bias voltage to each microphone (+) and (-) signal circuit for the operation of the microphone.
The radio provides the cellular phone microphone with a supplied voltage on the cellular phone microphone high signal circuit. When the microphone is in use, voice data from the user is sent back to the radio on the cellular microphone low signal circuit.
For Active Noise Cancellation System:
The 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 circuit for the 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.
What are the Possible Causes of the DTC B1277?
- Faulty Cellular Phone Microphone (For Cellular, Entertainment, and Navigation Systems)
- Faulty Radio Volume Compensator Interior Noise Microphone (For Active Noise Cancellation System)
- Faulty Audio Amplifier (For Active Noise Cancellation System)
- Faulty Human Machine Interface Control Module or Radio (For Cellular, Entertainment, and Navigation Systems)
How to Fix the DTC B1277?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B1277 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- B1277 Acura — Headlight Switch AUTO Position Circuit Malfunction
- B1277 Buick — Microphone 1 Input Signal Circuit
- B1277 Cadillac — Microphone 1 Input Signal Circuit
- B1277 Chevrolet — Microphone 1 Input Signal Circuit
- B1277 Ford — Reverse Lamp Circuit Short
- B1277 GMC — Microphone 1 Input Signal Circuit
- B1277 Honda — Headlight Switch AUTO Position Circuit Malfunction
- B1277 Lincoln — Reverse Lamp Circuit Short
- B1277 Mercury — Reverse Lamp Circuit Short
Frequently Asked Questions about B1277 Code
1. What are common symptoms of OBDII code B1277 (Microphone 1 Input Signal Circuit)?
The common symptoms include issues with the vehicle's hands-free calling system, poor sound quality during phone calls, and a malfunctioning voice command system.
2. What are the possible causes of OBDII code B1277?
Possible causes of this code include a faulty microphone, damaged wiring or connectors in the microphone circuit, or a malfunctioning audio control module.
3. How can I diagnose the issue related to OBDII code B1277?
To diagnose the issue, start by checking the microphone and its connections for any visible damage. Next, use a multimeter to test the continuity of the wiring in the microphone circuit. Finally, check the audio control module for any faults.
4. Can I repair OBDII code B1277 on my own?
Depending on your skill level and access to tools, you may be able to repair this code on your own. If the issue is a simple wiring connection problem, you might be able to fix it yourself. However, for more complex issues like a faulty audio control module, professional help may be necessary.
5. Is it safe to continue driving with OBDII code B1277 present?
While OBDII code B1277 is not a critical safety issue, it can affect the functionality of your vehicle's hands-free calling and voice command systems. It is recommended to address the issue to ensure proper communication and safety while driving.
6. How much does it typically cost to repair OBDII code B1277?
The cost of repairing OBDII code B1277 can vary depending on the root cause of the issue. Simple fixes like repairing a wiring connection may be inexpensive, while replacing a faulty microphone or audio control module can be more costly.
7. Can extreme temperatures affect the occurrence of OBDII code B1277?
Extreme temperatures can potentially affect the components involved in the microphone circuit, leading to issues that trigger OBDII code B1277. It is important to keep the vehicle's interior at a moderate temperature to prevent such problems.
8. Will resetting the OBDII code B1277 resolve the issue permanently?
Resetting the code may temporarily clear the error message, but if the underlying issue causing OBDII code B1277 is not addressed, the problem is likely to reoccur. It is essential to diagnose and fix the root cause of the code for a permanent solution.
9. Can water damage cause OBDII code B1277 to appear?
Yes, water damage can potentially affect the microphone, wiring, or connectors in the circuit, leading to the appearance of OBDII code B1277. If your vehicle has been exposed to water, it is advisable to inspect these components for any damage.
10. How do I prevent OBDII code B1277 from occurring in the future?
To prevent OBDII code B1277 from occurring in the future, regularly inspect the microphone and its connections for any signs of wear or damage. Additionally, keeping the vehicle's interior well-maintained and protected from extreme conditions can help avoid this issue.
Discuss the causes and fixes for B1277 OBDII Code
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this code B1298 AND B1277 is poping up when i had the part store put it on the computer what is and how do i fix it i have a 1999 buick park ave ultra please help
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Unfortunately there is not information on the 1999 Buick Park Ave Ultra service manual for the B1298 and B1277 codes. Either you got the wrong information or the scanner it's not compatible with your model.
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