Tail Lights

MILTONSPORTS

MEMBER
2003 MERCURY MOUNTAINEER

2003 Mercury Mountaineer V8 All Wheel Drive 123000 miles

My name is Milton Smith and heres my problem. My tail light stop working, I replaced the tail lights but still not success, I replaced the fuse and they work for a while, but now it does not work, however the turn signals work, brake lights work, back up lights work etc but the tail lights and my dash board lights do not work and neither does it beeps when I open the door with the key in the ignition or informing me when the head lights is on all other interior lights work just the one where it shows speed odometer does not work

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

More than likely the fuse has blown again. The likely cause of this fuse to continue to blow is there is a short in the circuit.

So, in order to find this, we need to start with inspecting the connectors for the taillights.

When these connectors have water intrusion or other corrosion then they can create a path to ground that does not pass through the lamp bulb, and this will cause the fuse to blow.

Here is a video that will show how to inspect them and replace them:

https://youtu.be/PxA5wczsCVo

Also, we need to know for sure which fuse is blowing. This will possibly cause us to go in a different direction so that is important information.

I am attaching the wiring diagrams below that will help figure this issue out.

However, we also need to check the other lights operation. Do the turn signals still work or any of the other lamps?

If not, then we may have an issue with the multifunction switch.

Let's start with this info and we can go from there.

Thanks

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