2002 ford explorer rear brake light problems
jonesrsrg
12-05-2008, 08:12 PM
hi all .
i have a 2002 ford explorer. The rear brake lights arnt working but the top brake light does work. i checked bulbs they are good. im not sure which fuse it is or even if the fuse is the really the problem. im stumped. ive read it might be the brake switch on the brake pedal but since the top beke light works kinda figuring that may not be the problem either. any help with this would be greatly apreciated. thanks again for answering all my other automotive ?s in the past . :banghead:
i have a 2002 ford explorer. The rear brake lights arnt working but the top brake light does work. i checked bulbs they are good. im not sure which fuse it is or even if the fuse is the really the problem. im stumped. ive read it might be the brake switch on the brake pedal but since the top beke light works kinda figuring that may not be the problem either. any help with this would be greatly apreciated. thanks again for answering all my other automotive ?s in the past . :banghead:
shorod
12-06-2008, 12:00 PM
On your 2002, the Center High Mount Stop Lamp (CHMSL) is connected directly to the stop lamp switch in parallel with the multi-function switch. The remaining brake lights are powered via the multi-function switch.
If you have a multimeter or test light, I would suggest you check for power to terminal 2 of the multi-function switch (MFS) with the brake pedal depressed, then also at terminals 6 and 7 of the MFS. If you have good voltage there, then check for voltage to the bulbs in the rear. If using a test light, you'll be safe, but if using a Multimeter, the high input impedance of the meter may give you a false reading as it won't load the circuit.
If you have power from the MFS but not at the brake light bulbs, you'll need to trace the wires to determine where the open/corrosion is. If you have aftermarket trailer wiring installed and they didn't use the factory-provided connection, I'd start in the area of the trailer wiring splices.
-Rod
If you have a multimeter or test light, I would suggest you check for power to terminal 2 of the multi-function switch (MFS) with the brake pedal depressed, then also at terminals 6 and 7 of the MFS. If you have good voltage there, then check for voltage to the bulbs in the rear. If using a test light, you'll be safe, but if using a Multimeter, the high input impedance of the meter may give you a false reading as it won't load the circuit.
If you have power from the MFS but not at the brake light bulbs, you'll need to trace the wires to determine where the open/corrosion is. If you have aftermarket trailer wiring installed and they didn't use the factory-provided connection, I'd start in the area of the trailer wiring splices.
-Rod
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