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 there's a problem with the part of the car that helps charge the battery. It's like a switch isn't working right, and it needs to be fixed so the battery can charge properly.
The P2D73 code indicates an issue with the control circuit for the negative contactor in the battery charging system, which might be open or malfunctioning.
The P2D73 code is triggered when the Engine Control Module (ECM) detects a malfunction in the control circuit for the negative contactor D of the battery charging system. This could be due to an open circuit or a failure in the contactor itself, preventing proper charging of the vehicle's battery.
• Battery not charging
• Warning light on the dashboard
• Possible vehicle starting issues
• Faulty negative contactor
• Open circuit in the control wiring
• Damaged ECM or control module
Contactor: A switch used to control the flow of electricity in a circuit.
ECM: Engine Control Module, the computer that controls engine functions.
• Check the wiring and connectors for any open circuits or damage.
• Test the negative contactor for proper operation.
• Inspect the ECM for any faults or damage.
• Repair or replace damaged wiring or connectors.
• Replace the faulty negative contactor.
• Reprogram or replace the ECM if necessary.
• Multimeter
• OBD-II scanner
• Wiring diagram
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections.
• Ensure proper maintenance of the charging system.
• Keep the ECM firmware updated.
Electrical Circuit Issue
• Avoid running the vehicle with a known charging issue.
• Seek professional diagnosis if unsure about repairs.
Check with your vehicle manufacturer as battery and charging system components may be covered under warranty.
This code has been historically associated with hybrid and electric vehicles, where the battery charging system is critical.
High – This issue can lead to battery failure and vehicle starting problems.
Driving with a malfunctioning charging system can lead to vehicle breakdowns and safety hazards.
• Vehicle in a safe, stationary position.
• Battery fully charged or connected to an external charger.
The negative contactor is typically located near the battery or within the battery management system.
Q: Can I drive my car with this code?
A: It's not recommended, as it can lead to battery failure and leave you stranded.
Q: Will this code clear itself?
A: No, the issue needs to be fixed before the code can be cleared.
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