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 found a problem with the part that helps change gears. It's like a toy with a broken switch that can't turn on.
This code indicates a short circuit in the transmission range select motor control circuit, which affects the vehicle's ability to select the correct gear.
The P18E8 code is triggered when the Powertrain Control Module (PCM) detects a short circuit in the transmission range select motor control circuit. This motor is responsible for moving the transmission into the correct gear based on the driver's input. A short circuit can cause incorrect or no gear selection, leading to drivability issues.
• Check Engine Light is on
• Vehicle stuck in one gear
• Transmission shifting issues
• Faulty transmission range select motor
• Damaged wiring or connectors in the circuit
• Faulty Powertrain Control Module (PCM)
PCM: Powertrain Control Module, the computer that controls the engine and transmission.
Short Circuit: An electrical circuit that allows a current to travel along an unintended path with no or a very low electrical impedance.
• Scan the vehicle for codes and freeze frame data.
• Inspect the wiring and connectors for damage or corrosion.
• Test the transmission range select motor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty transmission range select motor.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect and maintain transmission wiring.
• Avoid harsh driving conditions that can damage the transmission.
• Ensure proper vehicle servicing and maintenance.
Electrical Circuit Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional mechanic.
• Avoid driving the vehicle until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been known to appear in vehicles with high mileage or those frequently used in heavy-duty applications.
High – This issue can lead to transmission failure or unsafe driving conditions.
Driving with a faulty transmission can be dangerous and may lead to further vehicle damage.
• Vehicle in park or neutral
• Engine running
The transmission range select motor is typically located on the transmission housing.
Q: Can I drive with a P18E8 code?
A: It's not recommended as it can lead to unsafe driving conditions.
Q: How can I prevent this code from appearing?
A: Regular maintenance and inspection of the transmission system can help prevent this issue.
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