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 has detected a problem with the part that helps the car shift from 5th gear to 4th gear. It's like when a bicycle chain gets stuck and you can't change gears smoothly.
The P1874 code is triggered when the transmission control module (TCM) detects a high voltage signal from the 5-4 shift solenoid circuit, indicating an electrical issue.
The P1874 code indicates that the transmission control module has detected a high voltage condition in the 5-4 shift solenoid circuit. This could be due to a short circuit, open circuit, or a faulty solenoid. The shift solenoid is responsible for controlling the hydraulic flow to change gears in the automatic transmission.
• Check Engine Light is on
• Transmission may not shift properly
• Decreased fuel efficiency
• Faulty 5-4 shift solenoid
• Open or shorted wiring in the shift solenoid circuit
• Poor electrical connection in the shift solenoid circuit
Transmission Control Module (TCM): A computer that controls the transmission's operation.
Shift Solenoid: An electromechanical component that controls the flow of transmission fluid to change gears.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the 5-4 shift solenoid for proper operation.
• Replace the faulty 5-4 shift solenoid.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect and maintain transmission fluid levels.
• Check for wiring damage during routine maintenance.
• Ensure proper electrical connections in the transmission system.
Transmission Issue
• Avoid driving the vehicle until the issue is fixed to prevent further damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for specific warranty coverage on transmission components.
The P1874 code has been associated with vehicles using electronically controlled automatic transmissions, particularly in GM models.
Moderate – It is advisable to address this issue soon to prevent potential transmission damage.
Ignoring transmission issues can lead to safety hazards and may result in costly repairs.
• Engine running
• Vehicle in drive
The 5-4 shift solenoid is located inside the transmission, typically accessible by removing the transmission pan.
Q: Can I drive with a P1874 code?
A: It's not recommended to drive with this code, as it can lead to further transmission damage.
Q: How do I clear a P1874 code?
A: After repairs, use an OBD-II scanner to clear the code. If the problem is fixed, it should not return.
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