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 gear shift lever. It's like when a video game controller isn't working right, and you can't move your character properly.
The P1877 code indicates that the voltage in the circuit for the gear selector lever is higher than expected.
The P1877 code is triggered when the Powertrain Control Module (PCM) detects an unusually high voltage in the Gear Selector Lever (GSL4) circuit. This could be due to a short circuit, a faulty sensor, or a wiring issue.
• Check Engine Light is on
• Difficulty shifting gears
• Transmission stuck in one gear
• Faulty gear selector lever sensor
• Short circuit in the wiring
• Damaged or corroded connectors
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
GSL4: Gear Selector Lever 4
• Use an OBD-II scanner to confirm the code.
• Inspect the gear selector lever and its wiring for damage.
• Check the voltage levels in the GSL4 circuit.
• Replace the gear selector lever sensor if faulty.
• 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
• Screwdriver set
$150 - $400
Moderate
• Chevrolet Silverado
• Ford F-150
• Toyota Camry
• Regularly inspect and maintain the gear selector lever.
• Ensure wiring and connectors are secure and free of corrosion.
• Avoid forcing the gear lever.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if you experience shifting issues.
Check with the vehicle manufacturer for warranty coverage on transmission components.
The P1877 code has been associated with issues in vehicles with electronic gear shift systems, particularly as these systems age.
Moderate – While the vehicle may still be drivable, it is important to address the issue to prevent further transmission damage.
Driving with transmission issues can be unsafe. Address the problem promptly to ensure vehicle safety.
• Vehicle in park or neutral.
• Engine running and warmed up.
The gear selector lever is located in the vehicle's cabin, typically between the driver and passenger seats.
Q: Can I drive with a P1877 code?
A: It's not recommended to drive with this code as it may lead to further transmission issues.
Q: How do I reset the P1877 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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