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 having trouble checking a part that helps stop fuel from going to the engine when needed.
The engine control module (ECM) performs a self-test to ensure all systems are functioning correctly. This code indicates a failure in the self-test related to the fuel cut-off circuit.
The P1601 code is triggered when the ECM detects an issue during its self-test with the fuel cut-off circuit, which is responsible for stopping the fuel supply to the engine under certain conditions, such as during an accident or when the vehicle is turned off.
• Check Engine Light is on
• Engine may not start
• Possible stalling
• Faulty ECM
• Damaged fuel cut-off relay
• Wiring issues in the fuel cut-off circuit
ECM: Engine Control Module
Relay: An electrically operated switch
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors in the fuel cut-off circuit.
• Test the fuel cut-off relay for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty fuel cut-off relay.
• If necessary, replace the ECM.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $800
Moderate
• Toyota Camry
• Ford Focus
• Honda Accord
• Regularly inspect and maintain wiring.
• Ensure relays and fuses are in good condition.
• Perform routine diagnostic checks.
Engine Performance
• Avoid driving the vehicle until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer; ECM-related issues may be covered under warranty.
This code has been associated with ECM issues in various vehicle models, often due to wiring problems or relay failures.
High – This issue can prevent the vehicle from starting or cause it to stall unexpectedly.
Driving with this code can lead to unsafe conditions. Address the issue promptly to ensure vehicle safety.
• Engine off
• Battery fully charged
The ECM is usually located in the engine bay or under the dashboard. The fuel cut-off relay is often found in the fuse box.
Q: Can I drive with a P1601 code?
A: It's not recommended, as the vehicle may stall or fail to start.
Q: How do I reset the P1601 code?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
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