Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of the car that controls the valve for the alternative fuel tank. It's like a switch that isn't working right.
The P2A29 code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the control circuit of the alternative fuel tank shutoff valve C.
The alternative fuel tank shutoff valve is responsible for controlling the flow of alternative fuel to the engine. A 'circuit high' condition indicates that the voltage in the control circuit is higher than expected, which could be due to wiring issues, a faulty valve, or problems with the ECM.
• Check Engine Light is on
• Reduced fuel efficiency
• Difficulty in switching fuel types
• Faulty shutoff valve
• Wiring issues or short circuits
• Defective ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Scan for codes and freeze frame data
• Inspect wiring and connectors for damage
• Test the shutoff valve for proper operation
• Repair or replace damaged wiring
• Replace the faulty shutoff valve
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Wiring repair tools
$150 - $500
Moderate
• Toyota Prius
• Honda Civic Hybrid
• Chevrolet Volt
• Regular maintenance checks
• Inspect wiring for wear and tear
• Use quality fuel
Sensor Issue
• Have a professional diagnose the issue
• Avoid switching fuel types until resolved
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with hybrid and alternative fuel vehicles as they age, often due to wear and tear in the fuel system components.
Moderate – It should be addressed soon to prevent further issues.
Driving with a malfunctioning fuel system component can lead to increased emissions and potential safety hazards.
• Vehicle at operating temperature
• Alternative fuel system engaged
The alternative fuel tank shutoff valve is typically located near the fuel tank or along the fuel line.
Q: Can I drive with a P2A29 code?
A: It's not recommended to drive for extended periods with this code, as it may lead to increased emissions and reduced performance.
Q: How do I reset the P2A29 code?
A: After repairs, you can reset the code using an OBD-II scanner. However, if the issue is not fixed, the code will return.
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