Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the sensor that helps the car know what gear it's in. It's like when your game controller doesn't know which button you're pressing.
The code indicates that the voltage signal from the shift motor position sensor is lower than expected by the vehicle's computer.
The shift motor position sensor is responsible for providing the transmission control module (TCM) with the current position of the shift motor. When the TCM detects a voltage signal that is lower than the predefined threshold, it triggers the P28E9 code.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may enter limp mode
• Faulty shift motor position sensor
• Wiring issues such as shorts or open circuits
• Faulty transmission control module (TCM)
Shift Motor: A component that helps change gears in an automatic transmission.
Position Sensor: A sensor that detects the position of a component, such as a gear.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the shift motor position sensor with a multimeter.
• Replace the shift motor position sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regularly inspect and maintain transmission components.
• Ensure wiring and connectors are free from corrosion.
• Address any transmission issues promptly.
Sensor Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer for specific warranty coverage related to transmission components.
This code has been associated with sensor failures and wiring issues in vehicles with electronically controlled transmissions.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with a malfunctioning transmission can lead to safety hazards. It is recommended to have the issue diagnosed and repaired by a certified technician.
• Vehicle must be in a safe, stationary position.
• Ensure the engine is off before testing electrical components.
The shift motor position sensor is typically located on the transmission housing.
Q: Can I drive with a P28E9 code?
A: It's not recommended, as it can lead to further transmission issues.
Q: How do I clear the P28E9 code?
A: After fixing the issue, use an OBD-II scanner to clear the code.
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