Hi everyone,
I'm a new user and this is my first post- thanks for reading.
I have a 97 2.5d Disco 1 ( 96 P plate). He has clocked up over 247k miles and we have owned him for about 2 months. In the last week, with a strange electrical problem has developed.
I'm not too mechanical or electrically savvy, but I can describe the problem.

We have a problem whereby a number of electrical components stop working with no explanation. These include: Rear window heater, rear wiper, rear fog lamps, split level front sidelights, lights on "buzzer" ( when lights left on a door opened). Strangely enough, lights, wipers, horn , windscreen washers etc, carry on working?

If we disconnect the negative terminal of the battery and wait a moment and then reconnect - everything starts to work again. A few moments after driving it again, the same happens.

When the above stop working, the interia lights seem to have a life of their own - staying on for a while and then going off.

2 additional points which may help one of you "smarter than us" guys -

1. we recently replaced the old battery with a new heavy duty Bosch battery which fits fine and is holding a charge of over 12.5v.

2. Once the battery is reconnected, it seems to be fine until the engine is running again.

Could anyone give us any ideas ???

Thanks , Dave

 

There is a device on my 97 called the multi-function unit. About size of a pack of cigarettes. Snaps on back of fuse panel under the dash. It is a timer for lots of things, like the interior lights dimming down, the time delay for rear wiper, etc. The RAVE tells you how to force it into test mode, where it will cycle things.

 

Hi Savannah, thank for for taking some time to reply.
OK I have done the diagnostic test for the MFU and it runs through it with no problem.
But I guess it would do because I have just reconnected the battery and everything seems fine. Should I do it when I encounter the problem ( ie things not working) ?
Appreciate your views.
Dave

 

Yes, repeat when problem pops up. I took mine apart and there was a big power transistor that had no heat sink, it had melted a small hole in the side of the plastic case.

 

OK, are they very expensive to replace ?

 

I got one at boneyard, but dismantlers like Paul Grant also have them.