Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the electric circuit that controls the starter. It's like when a light switch is stuck and won't turn off the light.
The P1AA2 code indicates that the voltage in the starter unit control circuit is higher than expected.
The P1AA2 code is set when the powertrain control module (PCM) detects a high voltage condition in the starter unit control circuit. This could be due to a short circuit, a faulty starter relay, or issues with the wiring or connectors in the circuit.
• Engine may not start
• Check Engine Light is on
• Unusual clicking noise when trying to start the engine
• Faulty starter relay
• Short circuit in the starter control circuit
• Damaged wiring or connectors
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Check for any blown fuses related to the starter circuit.
• Inspect the starter relay for faults.
• Examine the wiring and connectors for damage or corrosion.
• Replace the faulty starter relay.
• Repair or replace damaged wiring or connectors.
• Clear the code and test the system.
• Multimeter
• OBD-II scanner
• Basic hand tools
$100 - $300
Moderate
• Chevrolet Volt
• Cadillac ELR
• Buick LaCrosse
• Regularly inspect electrical connections.
• Ensure battery terminals are clean and secure.
• Avoid overloading the electrical system.
Electrical Circuit Issue
• Do not attempt to repeatedly start the vehicle if the engine does not crank.
• Have the vehicle inspected by a professional if the Check Engine Light is on.
Check with the vehicle manufacturer for warranty coverage related to electrical components.
This code has been associated with issues in hybrid and electric vehicles where the starter circuit is more complex.
High – This issue can prevent the vehicle from starting, leaving you stranded.
Driving with a starter circuit issue can lead to unexpected vehicle shutdowns, which may be unsafe.
• Ensure the battery is fully charged.
• Perform tests in a controlled environment to prevent accidental starts.
The starter unit is typically located near the engine block, and the control circuit runs from the PCM to the starter relay and motor.
Q: Can I drive with a P1AA2 code?
A: It's not recommended as the vehicle may fail to start or shut down unexpectedly.
Q: How can I reset the P1AA2 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is fixed first.
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