B1286 – Servo Motor Potentiometer Airintake Left Circuit Short To Battery

The ODBII code B1286 indicates a short circuit in the left air intake servo motor potentiometer circuit, which is causing it to receive an unintended voltage from the battery.

The severity of ODBII code B1286 is moderate to high.

Common Causes For: B1285 Servo Motor Potentiometer Airintake Left Circuit Open

• Shorted wiring or connectors
• Faulty servo motor potentiometer
• Damaged or corroded electrical connections
• Malfunctioning air intake system components
• Issues with the vehicle’s control module
• Grounding problems in the circuit
• Incorrectly installed or aftermarket parts

Common misdiagnosis for B1286 Servo Motor Potentiometer Airintake Left Circuit Short To Battery

• Faulty servo motor
• Wiring issues or shorts in the harness
• Defective air intake sensor
• Malfunctioning engine control module (ECM)
• Incorrectly calibrated throttle position sensor
• Vacuum leaks in the intake system
• Issues with the intake manifold
• Problems with the vehicle’s electrical system or grounds

Common Troubleshooting Steps

The OBD-II code B1286 indicates a problem with the servo motor potentiometer circuit for the air intake system, specifically a short to battery in the left circuit. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Check the Vehicle’s Battery and Charging System:
• Ensure the battery is fully charged and in good condition.
• Check the alternator and charging system for proper operation.
• Inspect Wiring and Connectors:
• Visually inspect the wiring harness and connectors associated with the servo motor potentiometer circuit.
• Look for signs of damage, fraying, corrosion, or loose connections.
• Pay special attention to areas where the wiring may be exposed to heat or moving parts.
• Test the Potentiometer:
• Use a multimeter to test the resistance of the potentiometer. Compare the readings to the specifications in the vehicle’s service manual.
• Check for continuity in the potentiometer circuit to ensure there are no breaks.
• Check for Short Circuits:
• With the multimeter, check for continuity between the potentiometer circuit wires and the battery positive terminal. A short circuit will show continuity where there should be none.
• Inspect for any pinched or damaged wires that could be causing a short to battery.
• Inspect the Servo Motor:
• If applicable, check the servo motor for proper operation. Ensure it moves freely and is not jammed or obstructed.
• Test the motor’s resistance and operation according to the manufacturer’s specifications.
• Scan for Additional Codes:
• Use an OBD-II scanner to check for any additional trouble codes that may provide more context or indicate related issues.
• Clear Codes and Test Drive:
• After performing repairs or adjustments, clear the trouble codes using the OBD-II scanner.
• Take the vehicle for a test drive to see if the code reappears.
• Consult Service Manual:
• Refer to the vehicle’s service manual for specific diagnostic procedures and specifications related to the B1286 code.
• Seek Professional Help:
• If the issue persists after performing the above steps, consider seeking assistance from a qualified mechanic or automotive technician who can perform more in-depth diagnostics. By following these steps, you should be able to identify and resolve the issue related to the B1286 code.