P1201 – OBD-II DTC

OBD-II DTC P1201 – Key Off Voltage High

DTC P1201 meaning

DTC P1201 refers to a diagnostic trouble code indicating a “Key Off Voltage High” condition. This code is triggered when the Engine Control Module (ECM) detects a voltage level that is higher than expected when the ignition is turned off. This can indicate potential issues with the vehicle’s electrical system or components related to the fuel system.

DTC P1201 symptoms

Common symptoms associated with DTC P1201 may include:

• Check Engine Light illuminated
• Difficulty starting the engine
• Engine stalling or misfiring
• Increased fuel consumption
• Unusual engine performance

DTC P1201 causes

Several factors can lead to the triggering of DTC P1201, including:

• Faulty fuel pressure regulator
• Wiring issues or short circuits in the electrical system
• Defective ECM or software issues
• Faulty sensors, such as the fuel level sensor
• Corroded or loose electrical connections

DTC P1201 seriousness

DTC P1201 can be considered a moderate to serious issue. While it may not cause immediate engine failure, it can lead to poor engine performance and increased emissions. Ignoring this code may result in further damage to the vehicle’s fuel system or electrical components, potentially leading to more costly repairs.

How to diagnose DTC P1201

To diagnose DTC P1201, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1201 code.
2. Inspect the vehicle’s wiring and connectors for any visible damage or corrosion.
3. Check the fuel pressure regulator and associated components for proper operation.
4. Test the voltage levels at the ECM and related sensors with a multimeter.
5. Review the vehicle’s service history for any previous issues related to the fuel system or electrical components.

How to fix DTC P1201 step-by-step instructions

To fix DTC P1201, follow these steps:

1. Clear the DTC using an OBD-II scanner.
2. Inspect and repair any damaged wiring or connectors found during diagnosis.
3. Replace any faulty components, such as the fuel pressure regulator or sensors.
4. Ensure all electrical connections are secure and free of corrosion.
5. Test drive the vehicle to see if the code reappears.

How to erase DTC P1201

To erase DTC P1201, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the engine to verify if the code returns.

Recommended tools for OBD-II diagnostics

Explore our expert picks: The Best OBD2 Scanners for 2025

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.