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 getting a signal that's too high from the part that checks how fast the engine is going.
The Transmission Control Module (TCM) is detecting an unusually high signal from the engine speed sensor circuit.
P0739 indicates that the TCM has detected a voltage signal from the engine speed output circuit that is higher than the expected range. This could be due to a short circuit, a faulty sensor, or a problem with the wiring.
• Check Engine Light is on
• Transmission shifting issues
• Poor fuel economy
• Faulty engine speed sensor
• Short circuit in the wiring
• Malfunctioning TCM
TCM: Transmission 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 engine speed sensor for proper operation.
• Replace the engine speed sensor if faulty.
• Repair or replace damaged wiring.
• Replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Honda Accord
• Toyota Camry
• Ford Focus
• Regularly inspect and maintain wiring.
• Ensure sensors are clean and functioning.
• Schedule routine transmission checks.
Sensor Issue
• Drive cautiously until repaired.
• Avoid long trips until the issue is resolved.
Check if the vehicle's powertrain warranty covers sensor replacements.
This code has been associated with transmission issues in older vehicle models.
Moderate – Should be addressed soon to avoid further transmission issues.
Ignoring this code can lead to unsafe driving conditions.
• Vehicle must be running.
• Transmission in drive.
The engine speed sensor is usually located near the crankshaft or transmission.
Q: Can I drive with a P0739 code?
A: It's possible, but not recommended as it may lead to transmission damage.
Q: Will the Check Engine Light turn off after repair?
A: Yes, once the issue is fixed and the code is cleared, the light should turn off.
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