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 is having trouble reading the oil pressure in the engine. It's like when a video game controller isn't working right, so the game can't tell what you're trying to do.
The Engine Control Module (ECM) is detecting an issue with the signal from the oil pressure sensor or switch, indicating that the signal is out of the expected range.
The P2D91 code indicates a problem with the electrical circuit of the Engine Oil Pressure Sensor/Switch C. This could be due to a malfunctioning sensor, a wiring issue, or a problem with the ECM itself. The sensor is responsible for monitoring the oil pressure in the engine, and if it sends a signal that is outside of the expected parameters, this code is triggered.
• Check Engine Light illuminated
• Erratic oil pressure readings
• Engine performance issues
• Faulty oil pressure sensor/switch
• Wiring issues in the sensor circuit
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the oil pressure sensor with a multimeter.
• Replace the faulty oil pressure sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and change engine oil.
• Inspect wiring and connectors periodically.
• Use quality oil pressure sensors.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have a professional diagnose the issue if unsure.
• Regular maintenance can prevent such issues.
This issue may be covered under the vehicle's powertrain warranty. Check with your manufacturer.
This code has been associated with vehicles that have had oil pressure sensor issues, often due to faulty sensors or wiring problems.
Moderate – It is important to address this issue to avoid potential engine damage.
Driving with a faulty oil pressure sensor can lead to engine damage. Ensure repairs are made promptly.
• Engine at operating temperature
• Vehicle stationary
The oil pressure sensor is typically located near the oil filter or on the engine block.
Q: Can I drive with a P2D91 code?
A: It's not recommended to drive with this code active as it can lead to engine damage if the oil pressure is actually low.
Q: How do I reset the Check Engine Light after a repair?
A: You can reset the light using an OBD-II scanner or by disconnecting the battery for a few minutes.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
View on Amazon
Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
View on Amazon
Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.