B1246 – Dim Panel Potentiometer Switch Circuit Failure

The ODBII code B1246 indicates a failure in the dim panel potentiometer switch circuit, which controls the brightness of the dashboard lights.

The severity of ODBII code B1246 is generally considered moderate.

Common Causes For: B1245 Wiper Rear Motor Run Relay Circuit Short to Battery

• Faulty dimmer switch
• Wiring issues (shorts or open circuits)
• Poor connections or corroded terminals
• Malfunctioning body control module (BCM)
• Defective instrument cluster
• Grounding problems
• Voltage supply issues

Common misdiagnosis for B1246 Dim Panel Potentiometer Switch Circuit Failure

• Faulty dimmer switch
• Wiring issues or shorts
• Instrument cluster failure
• Body control module (BCM) malfunction
• Faulty headlight switch
• Poor ground connections
• Incorrectly calibrated or programmed BCM
• Malfunctioning dashboard lights

Common Troubleshooting Steps

The OBD-II code B1246 indicates a problem with the dim panel potentiometer switch circuit, which is responsible for controlling the brightness of the dashboard lights. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Check for Additional Codes: Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues.
• Inspect the Dimmer Switch:
• Check the dimmer switch for any visible damage or wear.
• Ensure that the switch is functioning properly by testing it with a multimeter. You should see a change in resistance as you adjust the dimmer.
• Examine Wiring and Connectors:
• Inspect the wiring harness and connectors associated with the dimmer switch for any signs of damage, corrosion, or loose connections.
• Look for frayed wires or broken connectors that could interrupt the circuit.
• Test the Circuit:
• Use a multimeter to test the voltage and ground at the dimmer switch and the associated wiring. Ensure that the circuit is receiving the correct voltage and that the ground is solid.
• Check for continuity in the wiring to ensure there are no breaks in the circuit.
• Check the Instrument Cluster:
• If the dimmer switch and wiring are functioning correctly, the issue may lie within the instrument cluster itself. Inspect the cluster for any signs of damage or malfunction.
• If possible, test the instrument cluster with a known good unit to see if the problem persists.
• Inspect Fuses:
• Check the fuses related to the dashboard lights and dimmer switch. A blown fuse could cause the circuit to fail.
• Look for Short Circuits:
• Inspect the circuit for any potential short circuits that could be causing the issue. This may involve checking for pinched wires or connections that are touching each other.
• Reset the Code:
• After performing any repairs or adjustments, clear the trouble code using the OBD-II scanner and take the vehicle for a test drive to see if the code returns.
• Consult Service Manual:
• Refer to the vehicle’s service manual for specific wiring diagrams and troubleshooting procedures related to the dim panel potentiometer switch circuit.
• Seek Professional Help:
• If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician for further diagnosis and repair. By following these steps, you should be able to identify and resolve the issue related to the B1246 code.