Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer that controls the transmission is having trouble following its instructions, kind of like when you forget the steps to a dance.
This code indicates that the Transmission Control Module (TCM) has detected an error in its program flow, which is monitored by a watchdog timer.
The Transmission Control Module (TCM) uses a watchdog timer to ensure that its internal processes are running correctly. If the program flow does not follow the expected path, the watchdog timer triggers a fault, resulting in this error code.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may go into limp mode
• Software glitch in the TCM
• Faulty TCM
• Electrical issues such as poor connections or damaged wiring
TCM: Transmission Control Module
Watchdog Timer: A timer used to detect and recover from computer malfunctions
• Use an OBD-II scanner to confirm the code
• Check for any other related codes
• Inspect the TCM and its wiring for damage or poor connections
• Reprogram or update the TCM software
• Repair or replace damaged wiring
• Replace the TCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$300 - $1000
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regularly update vehicle software
• Ensure proper maintenance of electrical systems
• Avoid harsh driving conditions that may stress the transmission
Transmission Control Module Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving the vehicle if it goes into limp mode
Check with the manufacturer for possible warranty coverage on the TCM.
This code has been associated with software-related issues in TCMs in various vehicles.
Moderate – It should be addressed soon to prevent further transmission issues.
Driving with a malfunctioning transmission control module can lead to unsafe driving conditions.
• Vehicle at operating temperature
• Vehicle in drive mode
The Transmission Control Module is typically located near the transmission or under the hood.
Q: Can I drive with a P17C0 code?
A: It's not recommended as it can lead to further transmission issues and unsafe driving conditions.
Q: Will resetting the code fix the problem?
A: Resetting the code may temporarily clear the light, but it won't fix the underlying issue.
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