Hello everyone, I have a 2003 S-Type 4.2. The passenger side of the rear lights appears to be just fine. The drivers side appears to have issues. When the rear fog lights are turned on I lose all lights on the drivers side. When the rear fog lights are turned off there is a small glow on the drivers side fog light all the time. When the rear fog lights are turned off and the brakes are applied the element for the brake light (the two element bult) does change to the second element, however, that bulb gets extremely dim and the fog light turns on. Finally, when the fog lights are turned off and the brakes are applied both fog lights turn on.

Any help would be greatly appreciated.

 

It seems you have a bad earth connection on your rear light, drivers side. Check and clean connections, and all should be fine.

DF

 

Don't know how different the 03 is from the 05 but you may have one of a couple problems. First of all, are you totally sure that you have the correct bulbs? I don't recall any dual element bulbs in mine. The wrong bulbs have been known to fit, but then make the circuits act weird.
Also, I changed out my rear bulbs and made the mistake of accidently touching metal with the bulb "tray" causing a spark. Once the bulbs were fitted the tail lamps acted up like yours. I checked the fuses and had to replace two of them. After that, all was fine again. You need to remember that there are circuits that interconnect the left and right tail lamps.

Hope it helps. Should be a real easy fix.