I bought my '88 240DL new and just blew by 380,000 miles. Original engine, second tranny. I have been experiencing various electrical "hiccups" within the last two weeks: brake lights do not work, master door lock works intermittently (I sometimes am required to forcefully pull up on the other door locks in order to open them), antenna works sporatically. I've heard about the contacts that are behind the ignition switch becoming loose and was thinking of starting there. The brake bulbs and fuses have been replaced, which should eliminate this as the culprit. Any assistance is much appreciated.

Hi Jim. I'm not so hot with the leccy bits but is it possible that the items you mention share a common earth that could be loose/corroding? Just a thought. Rich.

This might be a longshot, but since according to Haynes the fuses for the central locking and brake lights are right next to each other, they may be related by distance alone. Check to see if the connectors for those fuses (#7 and 8) are corroded. Also check for proper connection with the fuses which may be corroded as well, causing intermittent problems. The taillight circuit is on fuse 9 so you might as well check that one. A good cleaning could take care of all of those problems at once. Also, like John Sergeant said, it could be bad relays, so definitely check that stuff. Good luck.

The Lamp Failure Relay may be the cause of no brake lights. I had one fail on my 745T. On 700 series, electricity for the brake lights comes in on terminal 54, and goes out on terminals 54L and 54R. The Central Locking Relay may be the cause of your locking/unlocking problems as it was on the wife's 745T.