1997 Ford Mondeo Rear Lights

therookiefal

Hello all, I once again need to draw on the collective wisdom of boards. I have a 1997 Ford Mondeo, and I was driving home along the back of the airport and an unmarked Garda car flashed me and pulled me over. They, it must be said, very politely told me that my rear lights were not working (yes they were on!) but that my break lights were working fine. I stuck on the fog lights and drove home.
So I have taken the car home, and first checked all the bulbs. They all still work (as when you put on the parking lights, the bulb that should be the rear light works) and as said the break lights and fog lights work. So next up, I checked the fuses and they all seem fine as well, and I did a bit of swapping about to make sure that they were working. This didn't resolve the issue.
Also, it must be said, that recently, the dash illumination has failed as well (changed that fuse as well, and still broken), and the air bag light did flash intermittently, but luckily I got the answer to fix that off boards....

I don't want to take it to a dealer for what I hope is something minor, and I am trying to sell the car and don't want the expense of it....thanks in anticipation....

Blue850

Are the front park lights working? if not I'd suspect the light switch is at fault

alias no.9

The tail lights, front sidelights and instrument panel lights are generally on the same fuse so if the side lights and instrument panel lights are ok, it's local to the back of the car. It could be the earth connection at the back lights.

therookiefal

Yep, all the front lights work fine including parking and fog lights. If the light switch was broken, would that not mean both front and back would be gone? Or could there essentially be 1 switching mechanism for the front and one for the back?

The side lights work fine, but will go and have a fiddle in the back and see if any earth connection problems jump out at me!?!?!

Also to add, when I get out of the car, and you left the lights on, wehn you opened the drivers door, and alarm would bong to warn you the lights were still on, but it has stopped doing that too, instead now when you take the keys out of the ignition, the lights go off automatically ie. you can't have the lights on without the keys in it....and the bong is gone too....

Is the beginning of a death of a 10 year old mondeo with just 98k on the clock!?

alias no.9

therookiefal wrote:

The side lights work fine, but will go and have a fiddle in the back and see if any earth connection problems jump out at me!?!?!

Car electrics usually use the metal bodywork of the car as a common ground. The negative terminal of the battery is connected directly to the body work. They run a single power wire to each device which connects to the positive terminal of the device while the negative terminal is either connected directly to the bodywork or connected to the body work via a short wire, completing the circuit back to the negative terminal of the battery.

So in short, what you're looking for is a short wire coming from the connector for the tail lights that is bolted onto the bodywork. Check for corrosion on it, the most likely culpret. If it is corroded, undo it rub with some sandpaper and refit it.

therookiefal

right so, that sounds like a possibilty, as another problem that is common to Mondeo is a leaky boot lid, so maybe water has got into the brain of the lights...will try tomorrow morn.

mondeoman

therookiefal wrote:

right so, that sounds like a possibilty, as another problem that is common to Mondeo is a leaky boot lid, so maybe water has got into the brain of the lights...will try tomorrow morn.

Its more likely the seals on the light clusters have perished (not boot lid).its very common on '96-'00 mondeos.very easy to fix with tiger seal or silicone.
if your near Gorey i'll do it for you;)