The parking, taillight, license plate and brake lights are not working?

CLEEZYWEEZY33

MEMBER
1998 LINCOLN TOWN CAR
4.6L
V8
2WD
AUTOMATIC
170,000 MILES

It all started when I noticed my car listed above car hoopty series’ taillights weren’t working. Then I noticed the brake lights weren’t working either although the third brake light does. I changed the multi-function switch and the turn signals and hazards both work. Headlights work but no parking lights whatsoever. I changed the brake light switch and noticed the harness was melted so I swapped that out too. I’ve pulled every fuse and none are blown. So here is what I got:

Not working:
Parking lights
Taillights
Lower brake lights (third brake light works)
License plate light

What does work:
Headlights
Reverse lights
Turn signals
Hazards

Saturday, March 29th, 2025 AT 6:59 PM

1 Reply

STEVE W.

MECHANIC
15,233 POSTS

As shown in the attached you can see the brown wire is the feed to all of the tail and marker lights that are out. From the melted harness and light failure, it sounds like the lighting control module has likely burnt out from a load on it. The brake lights are all fed from the same switch and fuse. So that switch and fuse are OK. It then feeds the dark green that goes through the switch and to the lights on 2 different circuits.
You say it has nonstock taillights? If so, then it is possible that something in them shorted and caused an overload.

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