B1045 2018 GMC Sierra Code - Left Rear Door Audio Output 3 Circuit
Quick Answer
Vehicles without Amplifier: Each of the audio output channel circuits (+) and (-), at the radio have a DC bias voltage that is approximately one-half of battery voltage. Common causes include Faulty Radio Unit, Faulty Audio Amplifier (If equipped), Faulty Left Rear Door Speaker (Subwoofer for vehicles with Amplifier). 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
- B1045 2018 GMC Sierra indicates Left Rear Door Audio Output 3 Circuit.
- Common causes
- Common causes include Faulty Radio Unit, Faulty Audio Amplifier (If equipped), Faulty Left Rear Door Speaker (Subwoofer for vehicles with Amplifier).
- 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 B1045 2018 GMC Sierra Description
Each of the audio output channel circuits (+) and (-), at the radio have a DC bias voltage that is approximately one-half of battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5 V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. The frequency (Hz) of the AC voltage signal is directly related to the frequency of the input (audio source playing) to the audio system. Both the DC bias voltage and the AC voltage signals are needed for the audio system to properly produce sound.
Vehicles with Amplifier:
The Media Oriented Systems Transport (MOST) is a high-speed multimedia network technology. The serial MOST bus uses a ring topology and synchronous data communication to transmit audio, video, data and control information between any devices attached.
The audio amplifier is a participant on the MOST network. The audio amplifier receives audio input and control information from the MOST bus.
Each of the audio output channel circuits (+) and (−), at the audio amplifier have a DC bias voltage that is approximately one-half of the battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound.
What are the Possible Causes of the DTC B1045 2018 GMC Sierra?
- Faulty Radio Unit
- Faulty Audio Amplifier (If equipped)
- Faulty Left Rear Door Speaker (Subwoofer for vehicles with Amplifier)
- Left Rear Door Speaker (Subwoofer for vehicles with Amplifier) harness is open or shorted
- Left Rear Door Speaker (Subwoofer for vehicles with Amplifier) circuit poor electrical connection
How to Fix the DTC B1045 2018 GMC Sierra?
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
B1045:02 Left Rear Door Audio Output 3 Circuit Short to Ground
B1045:04 Left Rear Door Audio Output 3 Circuit Open
User Submitted Video
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B1045 2018 GMC Sierra 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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Frequently Asked Questions about B1045 2018 GMC Sierra Code
1. What does the OBDII code B1045 mean on a 2018 GMC Sierra?
The code B1045 indicates an issue with the Left Rear Door Audio Output 3 Circuit, which is related to the audio system in the vehicle.
2. What are the common symptoms of code B1045 in a 2018 GMC Sierra?
Common symptoms include no sound or distorted audio from the left rear door speaker or intermittent audio performance.
3. What causes the B1045 code to appear on a 2018 GMC Sierra?
This code is typically caused by a faulty speaker, damaged wiring, a poor connection, or an issue with the amplifier or audio control module.
4. Can a blown speaker trigger the B1045 code?
Yes, a blown or damaged left rear door speaker can trigger this code due to an open or shorted circuit.
5. How can I diagnose the B1045 code in my 2018 GMC Sierra?
Diagnose the issue by inspecting the left rear door speaker, checking the wiring and connectors for damage, and testing the circuit for continuity or shorts.
6. Is the amplifier a potential cause of the B1045 code in a 2018 GMC Sierra?
Yes, a malfunctioning amplifier can cause this code if it fails to properly send audio signals to the left rear door speaker.
7. Can I still drive my vehicle with the B1045 code?
Yes, the vehicle can still be driven, but you may experience audio issues from the left rear door speaker.
8. How do I fix the B1045 code on a 2018 GMC Sierra?
Fixes include replacing the faulty speaker, repairing damaged wiring, ensuring proper connections, or replacing the amplifier if necessary.
9. Can clearing the code resolve the problem?
Clearing the code may temporarily remove the warning, but the underlying issue must be fixed to prevent the code from returning.
10. Should I take my 2018 GMC Sierra to a professional for the B1045 code?
If you're unable to diagnose or repair the issue yourself, it’s recommended to take the vehicle to a professional technician for further inspection.
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