iGotcha

I am having a problem with my brake lights and hazzards not working. The turn signals work and when you turn on the lights, the lights in the back come on. I've checked the fuses under the dash, replaced the brake light switch and changed the bulbs. Does anyone have any ideas on what is wrong?

ethosb

Under the hood on the drivers side there should be a black box with additional fuses in it. It is called the PDB or Power Distribution Box. Check the fuses and I bet you will find the blown one.

89F150

What do you mean when you turn the lights on, the lights in the back come on?

iGotcha

Tail lights

iGotcha

I found a black box under the hood on the drivers side but I don't think it has any fuses. Only thing I see are wires that go into the box. Is that it and if it is how do I get to the fuses?

LunaticSVT

******Brake Lights*******
Possible Source(s) of failure/problems are the central Junction Box Fuse 13 (20A), Circuitry or the BPP switch.

If it is not the fuse then check to see if the BPP switch is attached to the brake pedal arm. You will have to get on your back. If not connected then obviously reconnect. If connected run a test on it. Remove the switch and connect a 10A fused jumper wire between C252 pin 5, circuit 10 (LG/RD), harness side, and C252 pin 4, circuit 511(LG), harness side. (see attached pic1).

Check to see if the stop lights are operational. If they are then replace the BPP sensor on the pedal arm.

You can also check the connector pin 5 to see if it is getting 10v. If it is not then more than likely it is wiring issue, if you have already checked/replaced fuse.


*****HAZZARD LAMPS*****

Possible Source(s) of failure CJB Fuse 23 (10A), Circuitry, Multifunction switch or the Electronic flasher.

Check the fuse first, then the Electronic flasher unit and then check to see if that the MF switch is seated properly. If this is all correct then it will more than likely be a wiring issue. That is not going to be fun.

BTW welcome to FordForums.
LunaticSVT