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 computer in your car is having trouble talking to a sensor that helps it know how the gears are moving.
The P173E code is triggered when the transmission control module (TCM) detects a low voltage signal from the shift rod 1/3 sensor circuit.
The shift rod 1/3 sensor is responsible for providing feedback to the TCM about the position of the shift rods. A low circuit signal indicates that the sensor is not sending the expected voltage back to the TCM, which could be due to a wiring issue, a faulty sensor, or a problem with the TCM itself.
• Check engine light on
• Transmission may not shift properly
• Possible limp mode activation
• Faulty shift rod 1/3 sensor
• Wiring issues or poor connections
• Faulty transmission control module (TCM)
TCM: Transmission Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the shift rod 1/3 sensor.
• Test the shift rod 1/3 sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the shift rod 1/3 sensor if faulty.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance checks
• Ensure proper transmission fluid levels
• Inspect wiring for damage
Sensor Issue
• Avoid driving the vehicle until repaired.
• Consult a professional mechanic for diagnosis.
Check with your vehicle manufacturer for specific warranty coverage on transmission components.
This code has been associated with transmission sensor issues in vehicles with automated manual transmissions.
Moderate – It should be addressed soon to prevent further transmission issues.
Driving with transmission issues can be dangerous and may lead to more severe mechanical problems.
• Engine running
• Transmission in various gear positions
The shift rod 1/3 sensor is typically located within the transmission housing.
Q: Can I drive with a P173E code?
A: It's not recommended as it may cause transmission issues or further damage.
Q: How do I reset the P173E code?
A: Fix the underlying issue, then use an OBD-II scanner to clear the code.
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