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 electrical circuit that controls shifting from 4th gear to 3rd gear. It's like if your remote control wasn't sending the right signal to change the TV channel.
The P1873 code is set when the transmission control module (TCM) detects a high voltage condition in the circuit responsible for shifting from 4th to 3rd gear.
The P1873 code indicates an issue with the transmission's shift solenoid circuit, specifically related to the 4-3 shift. A 'high' signal typically means there is more voltage than expected, which could be due to a short circuit, open circuit, or a malfunctioning solenoid.
• Harsh or delayed shifting
• Transmission stuck in one gear
• Check Engine Light illuminated
• Faulty shift solenoid
• Wiring issues such as shorts or opens in the circuit
• Faulty transmission control module (TCM)
TCM: Transmission Control Module
Solenoid: An electromechanical device used to control fluid flow in the transmission
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the shift solenoid for proper operation.
• Replace the faulty shift solenoid.
• Repair or replace damaged wiring or connectors.
• Replace or reprogram the TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular transmission fluid changes
• Routine electrical system inspections
• Avoiding excessive towing or heavy loads
Transmission Control System Issue
• Avoid driving at high speeds until the issue is fixed.
• Consult a professional mechanic for a thorough diagnosis.
Check with the vehicle manufacturer for transmission-related warranties.
The P1873 code has been associated with transmission issues in vehicles with automatic transmissions, particularly in older models.
Moderate – While the vehicle may still be drivable, it is recommended to address this issue promptly to avoid further transmission damage.
Driving with a malfunctioning transmission can be dangerous and may lead to further damage. Always ensure your vehicle is safe to operate.
• Vehicle at operating temperature
• Transmission in drive mode
The shift solenoid is located inside the transmission, typically accessible by removing the transmission pan.
Q: Can I drive with a P1873 code?
A: It's possible to drive short distances, but it's not recommended due to potential transmission damage.
Q: How do I clear a P1873 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, the code should not return.
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