Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is saying that a part that helps control the timing of the engine is not working right. It's like a switch that is stuck in the 'on' position.
The code P104B indicates that the control circuit for the camshaft position timing pressure accumulator shutoff valve is experiencing a high voltage condition.
This code is triggered when the Powertrain Control Module (PCM) detects a higher than expected voltage in the control circuit for the camshaft position timing pressure accumulator shutoff valve. This valve is part of the variable valve timing system, which adjusts the timing of the camshaft to optimize engine performance and efficiency.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty camshaft position timing pressure accumulator shutoff valve
• Wiring issues such as short circuits or open circuits
• Faulty PCM or ECM
PCM: Powertrain Control Module
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the camshaft position timing pressure accumulator shutoff valve.
• Repair or replace damaged wiring or connectors.
• Replace the camshaft position timing pressure accumulator shutoff valve if faulty.
• Reprogram or replace the PCM/ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• BMW 3 Series
• Audi A4
• Volkswagen Passat
• Regular maintenance and inspection of the engine's electrical system.
• Ensure timely oil changes to prevent sludge buildup.
• Avoid driving with low oil levels.
Sensor Issue
• Do not ignore the Check Engine Light; have the vehicle inspected as soon as possible.
• Avoid hard driving until the issue is resolved.
• Keep track of fuel consumption for any unusual changes.
Check with the vehicle manufacturer for warranty coverage on engine components.
This code is relatively uncommon and often associated with vehicles that have advanced variable valve timing systems.
Moderate – It is recommended to address this issue soon to prevent potential engine performance problems.
Driving with a malfunctioning engine component can lead to increased emissions and potential safety risks.
• Engine running
• Vehicle in a safe and stable condition
The camshaft position timing pressure accumulator shutoff valve is typically located near the camshaft or within the engine's valve cover.
Q: Can I drive my car with a P104B code?
A: It's not recommended to drive for extended periods with this code, as it may lead to poor engine performance and increased fuel consumption.
Q: How can I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scanner to clear the code, or disconnect the battery for a few minutes to reset the system.
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