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Q: Rear Brake light and turn signal not working on driver side

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2011 F-150 Platinum. The rear brake light and turn signal is not working on the driver side. I have replaced the bulbs and the connectors but to no avail. I checked the fuses and they are fine as well. When I take my electronic key and unlock the truck the driver rear lights will not light up but when I lock the doors it does light up in the back. Need Help.... Never have seen this before.
My car has an automatic transmission.

A: Lighting problems like this can seem very c...

Lighting problems like this can seem very confusing, so it is best to start with the basics. Check for power and ground at the turn and brake light sockets. I suspect in your case you will have a good ground but you won’t have any power. If you discover there is a bad ground, this will be the simplest repair. The power side of these lamp circuit is from the BCM. (body control module) So if you don’t have power at the sockets, you will need to locate the BCM and check for power coming out of the BCM.

Before you do that, you will need to connect a scanner that can communicate with the BCM. Believe it or not, you could have a BCM code that is stopping your brake and turn signal lights from working. Most people don’t have access to a scanner that can access the BCM, so you will most likely need to book an appointment with us to do this. If there are no codes in the BCM, it is most likely the BCM that needs to be replaced. Before I went and replaced it, I would check all the power and grounds at the BCM.

BCM’s are common failure items on Fords, so it is likely the problem. But you will want to do due diligence and communicate with the BCM. I recommend the following inspection to help you out. Electrical components are not working

Be sure to send the technician a note about your exact issue so he or she can come best prepared for your repair.

Good luck!

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