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 using a backup plan because something isn't working right. It's like when you use a flashlight because the power went out.
The P1702 code is triggered when the transmission control module (TCM) detects a fault and switches to a substitute function to maintain vehicle operation.
P1702 indicates that the transmission control module has detected an issue with the transmission system and has engaged a substitute function to allow the vehicle to continue operating. This is a fail-safe mode to prevent damage to the transmission.
• Check Engine Light is on
• Transmission may not shift properly
• Reduced fuel efficiency
• Faulty transmission control module
• Wiring issues in the transmission system
• Defective transmission sensors
Transmission Control Module (TCM): A computer that controls the transmission's operation.
OBD-II Scanner: A device used to read diagnostic trouble codes from a vehicle's computer.
• Use an OBD-II scanner to confirm the code
• Inspect the transmission wiring and connectors
• Test the transmission control module
• Repair or replace damaged wiring
• Replace faulty transmission sensors
• Reprogram or replace the transmission control module
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $1000
Moderate
• Ford Focus
• Mazda 3
• Honda Accord
• Regular transmission maintenance
• Timely replacement of transmission fluid
• Routine inspection of transmission wiring
Transmission Control System Issue
• Do not ignore the Check Engine Light
• Have a professional diagnose the issue
• Avoid driving the vehicle if shifting becomes erratic
Transmission issues may be covered under powertrain warranty, check with the manufacturer.
The P1702 code has been associated with vehicles that have experienced transmission control module failures, particularly in older models.
Moderate – It is important to address this issue to prevent further transmission damage.
Driving with a faulty transmission can be dangerous and may lead to further damage. Consult a professional mechanic.
• Vehicle must be in operation
• Transmission must be shifting gears
The transmission control module is typically located near the transmission or under the vehicle's dashboard.
Q: Can I drive my car with a P1702 code?
A: It's not recommended to drive for long distances as it may cause further damage to the transmission.
Q: How do I reset the P1702 code?
A: You can reset the code with an OBD-II scanner, but it's important to fix the underlying issue first.
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