Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a switch in your car that helps control the wheels. It's like a light switch that isn't working right, and it's not sending the correct signals.
The P1816 code indicates that the vehicle's powertrain control module (PCM) has detected a low voltage condition in the wheel minus switch circuit.
The wheel minus switch is part of the vehicle's transmission control system. It is used to provide input to the transmission control module (TCM) regarding the wheel's rotational speed and direction. A low circuit error suggests that the voltage or signal from this switch is below the expected range, which can affect the vehicle's ability to shift gears properly.
• Check Engine Light illuminated
• Transmission may not shift properly
• Reduced fuel efficiency
• Faulty wheel minus switch
• Damaged wiring or connectors in the switch circuit
• Faulty transmission control module (TCM)
PCM: Powertrain Control Module
TCM: Transmission Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors related to the wheel minus switch for damage or corrosion.
• Test the wheel minus switch for proper operation.
• Replace the faulty wheel minus switch.
• Repair or replace damaged wiring or connectors.
• Replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$100 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly inspect electrical connections for corrosion.
• Ensure proper maintenance of the transmission system.
• Avoid harsh driving conditions that can stress the transmission.
Sensor Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with vehicles that have experienced transmission issues due to faulty sensors or wiring problems.
Moderate – Addressing this issue soon can prevent further transmission problems.
Ignoring transmission issues can lead to unsafe driving conditions. Always address check engine light warnings promptly.
• Vehicle at operating temperature
• Transmission in drive mode
The wheel minus switch is typically located near the transmission or wheel hub assembly.
Q: Can I drive with a P1816 code?
A: It's not recommended to drive with this code as it can lead to transmission issues.
Q: How do I reset the check engine light after fixing the issue?
A: Use an OBD-II scanner to clear the code after repairs are completed.
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