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 security system is stopping the electric motor from working. It's like when your toy won't work because the batteries are locked away.
The vehicle's immobilizer system, which is designed to prevent theft, is inhibiting the drive motor 'A' from generating torque.
The P1A99 code is triggered when the vehicle's immobilizer system sends a signal to disable the torque generation of the drive motor 'A'. This is a security feature to prevent unauthorized use of the vehicle.
• Vehicle will not start
• Warning light on the dashboard
• Inability to move the vehicle
• Faulty immobilizer system
• Malfunctioning key fob
• Issues with the vehicle's anti-theft system
Immobilizer: A security device that prevents a vehicle from starting unless the correct key is present.
Torque: A measure of rotational force in the engine.
• Check for any immobilizer system faults.
• Verify the key fob is functioning correctly.
• Inspect the anti-theft system for issues.
• Reprogram or replace the key fob.
• Repair or replace the immobilizer system.
• Reset the vehicle's anti-theft system.
• OBD-II scanner
• Multimeter
• Key fob programming tool
$150 - $500
Moderate
• Chevrolet Volt
• Nissan Leaf
• Toyota Prius
• Regularly check the key fob battery.
• Ensure the immobilizer system is functioning properly.
• Keep the vehicle's software updated.
Security System Issue
• Ensure your key fob is in good condition.
• Contact a professional if the vehicle does not start.
Check with the vehicle manufacturer for warranty coverage on security system components.
This code has been associated with vehicles using advanced anti-theft systems, particularly in hybrid and electric vehicles.
High – The vehicle may not start, requiring immediate attention.
Driving with a malfunctioning immobilizer system may lead to unexpected vehicle shutdowns.
• Vehicle in 'On' position
• Key fob present and functional
The immobilizer system is typically located near the ignition system or integrated within the vehicle's electronic control unit (ECU).
Q: What should I do if my car won't start due to this code?
A: Check if the key fob is working properly and consult a professional for further diagnosis.
Q: Can I drive my car with this code?
A: No, this code usually prevents the vehicle from starting or moving.
Budget · Bluetooth scanner
An app-based scanner with repair reports and enhanced system diagnostics on supported vehicles.
Helpful when live data and repair-report guidance can narrow down a drivability issue.
View on Amazon
Specialty · Fuel pressure tester
Helpful for no-start, lean, rich, injector, and fuel-delivery diagnosis.
Useful for checking whether fuel delivery is contributing to the fault.
View on Amazon
Specialty · Compression tester
Useful when misfire, mechanical condition, or low-cylinder-pressure problems are suspected.
Helpful when you need to rule out low compression or mechanical engine problems.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.
Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
View options on Amazon
Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.