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 inside your car that helps control the transmission is having trouble remembering things correctly.
The Transmission Control Module (TCM) uses RAM to store temporary data needed for transmission operation. An error in this memory can affect the TCM's performance.
The P1797 code indicates a fault in the RAM of the Transmission Control Module (TCM). This memory is crucial for storing temporary data that the TCM uses to manage transmission functions. A RAM error can lead to improper transmission operation.
• Check Engine Light is on
• Transmission shifting issues
• Erratic or harsh gear changes
• Faulty Transmission Control Module (TCM)
• Corrupted software or firmware
• Electrical issues such as poor connections or damaged wiring
Transmission Control Module (TCM): A computer that controls the automatic transmission.
Random Access Memory (RAM): Temporary memory used by computers to store data while they are operating.
• Use an OBD-II scanner to confirm the code.
• Inspect the TCM and its connections for damage or corrosion.
• Check for any available software updates for the TCM.
• Replace or reprogram the Transmission Control Module.
• Repair or replace any damaged wiring or connectors.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II Scanner
• Multimeter
• Screwdriver set
$300 - $1200
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly update TCM software.
• Ensure all electrical connections are secure and free of corrosion.
• Perform routine vehicle maintenance.
Transmission Control Issue
• Avoid driving aggressively until the issue is resolved.
• Consult a professional mechanic for a thorough diagnosis.
Check if your vehicle's powertrain warranty covers TCM issues.
This code has been associated with vehicles experiencing electronic control issues due to aging components or software glitches.
Moderate – Address the issue soon to avoid potential transmission damage.
Driving with a malfunctioning TCM can lead to unsafe driving conditions. Address the issue promptly.
• Engine running
• Vehicle in motion
The Transmission Control Module is usually located near the transmission or under the hood, depending on the vehicle model.
Q: Can I drive with a P1797 code?
A: It's possible, but not recommended. The transmission may not operate correctly, leading to unsafe driving conditions.
Q: How do I reset the TCM?
A: Disconnect the battery for a few minutes, then reconnect it. However, this may not solve the underlying issue.
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