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 is having trouble talking to a part that helps control the pressure in the transmission. It's like when your phone can't connect to Wi-Fi.
This code indicates a communication problem between the transmission control module and the secondary pressure solenoid, which manages hydraulic pressure in the transmission.
The P1749 code is triggered when the transmission control module (TCM) detects a communication error with the secondary pressure solenoid. This solenoid is responsible for regulating hydraulic pressure within the transmission, and a failure in communication can lead to improper transmission operation.
• Transmission slipping
• Harsh or erratic shifting
• Illuminated check engine light
• Faulty secondary pressure solenoid
• Wiring issues such as damaged connectors or broken wires
• Internal failure of the transmission control module
Transmission Control Module (TCM): An electronic component that controls transmission functions.
Solenoid: A device that converts electrical energy into mechanical movement.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors to the solenoid.
• Test the secondary pressure solenoid for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty secondary pressure solenoid.
• Replace or reprogram the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid changes
• Routine inspection of transmission components
• Prompt repair of any transmission-related issues
Transmission Control Issue
• Avoid driving the vehicle until repairs are made to prevent further damage.
• Consult with a professional mechanic for a thorough diagnosis.
Transmission components may be covered under the vehicle's powertrain warranty.
This code has been associated with transmission issues in vehicles with electronic control systems since the mid-1990s.
High – Transmission issues can lead to further damage and unsafe driving conditions.
Driving with transmission issues can be unsafe and may lead to further mechanical damage.
• Engine running
• Transmission in gear
The secondary pressure solenoid is located inside the transmission, usually accessible by removing the transmission pan.
Q: Can I drive with a P1749 code?
A: It's not recommended as it can cause further damage to the transmission.
Q: How do I reset the P1749 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is fixed first.
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