B1045:04 Code - Left Rear Door Audio Output 3 Circuit Open
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
- B1045:04 indicates Left Rear Door Audio Output 3 Circuit Open.
- 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 B1045:04 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.
The Diagnostic Trouble Code (DTC) will be set when an open is detected on the specified (+) (positive) or (−) (negative) signal circuit.
What are the Possible Causes of the DTC B1045:04?
- 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 B1045:04?
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 B1045:04 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 B1045:04 Code
What does the OBDII code B1045:04 mean?
The code B1045:04 indicates an open circuit issue in the Left Rear Door Audio Output 3, often related to the wiring or audio system components.
What are the symptoms of code B1045:04?
Typical symptoms include no sound or distorted audio from the left rear door speaker or a warning light related to the audio system.
What causes the B1045:04 code to appear?
Common causes include damaged wiring, disconnected connectors, a faulty left rear door speaker, or issues with the audio amplifier.
How can I diagnose the B1045:04 code?
Inspect the wiring and connectors for damage or disconnection, test the speaker functionality, and check the audio amplifier for faults.
Can I drive my vehicle with the B1045:04 code?
Yes, you can drive your vehicle, but the audio system may not function properly, affecting sound quality in the left rear door speaker.
How do I fix the B1045:04 code?
Repair or replace damaged wiring, reconnect loose connectors, replace a faulty speaker, or address issues with the audio amplifier.
Does the B1045:04 code require professional repair?
If you’re comfortable with basic electrical troubleshooting, you can attempt repairs. However, complex issues like amplifier failure may require professional assistance.
Could the B1045:04 code be caused by a software issue?
While rare, a software glitch in the audio system could potentially contribute to the problem, so it’s worth checking for updates or reprogramming.
How much does it cost to repair the B1045:04 code?
Repair costs vary depending on the issue, ranging from $50 for wiring repairs to $200 or more for speaker or amplifier replacement.
Will clearing the B1045:04 code fix the issue?
Clearing the code without addressing the underlying problem will not resolve the issue, and the code will likely reappear.
Discuss the causes and fixes for B1045:04 OBDII Code
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