B3950 GMC Code - Left Rear Turn Signal Circuit

When this code is triggered, you may notice that the left rear turn signal on your GMC vehicle does not illuminate or blink as intended.

Some common causes of this code include a faulty left rear turn signal bulb, a damaged wiring harness in the left rear turn signal circuit, or a defective turn signal flasher relay.

To diagnose the problem, start by inspecting the left rear turn signal bulb for any signs of damage. Then, check the wiring harness for any visible issues such as frayed wires or loose connections.

While a blown fuse in the left rear turn signal circuit can potentially cause this code, it is more likely to result in a loss of power to the turn signal rather than triggering the specific B3950 code.

It is not recommended to drive with this code active, as it indicates a malfunction in the left rear turn signal circuit, which can pose a safety hazard by affecting the visibility of your turning intentions to other drivers.

To repair this code, you may need to replace the left rear turn signal bulb, repair any damaged wiring in the circuit, or replace the turn signal flasher relay if it is found to be faulty.

Resetting the code may temporarily clear the issue, but if the underlying problem causing the code to be triggered is not addressed, it is likely to reappear upon the next diagnostic scan.

While this code can potentially occur in various GMC models, certain older vehicles or those with high mileage may be more susceptible to issues in the turn signal circuits.

Extreme weather conditions, such as heavy rain or snow, can sometimes contribute to electrical issues in the turn signal circuit, which may increase the chances of triggering this specific OBDII code.

Regularly inspecting and maintaining your vehicle's turn signal components, including bulbs and wiring, can help prevent issues that could lead to the triggering of OBDII code B3950 GMC.