97 Disco 1 strange electrical problem

Here is a weird one:
Engine running, headlights on, dash lights on, radio on, everything
normal.
If I open the driver's door the rear wiper starts up, the tach drops
to zero (no change in engine speed), the dash lights go off, the radio
goes off, the top switches on the left (rear defroster and fog lights,
I think) illuminate. If I turn off the headlights and then turn them
back on everything goes back to normal. I think the engine may
sometimes slow down and the dome light dim prematurely. Too many weird
things to count.
Just started acting up a day or so ago. Anyone suggest something I can
check?

Not sure but usually with wierd eletrical gremlins the earths are the first
things to look at.

Regards
Stephen

Gord Wedman composed the following ...
> Here is a weird one:
> Engine running, headlights on, dash lights on, radio on, everything
> normal.
> If I open the driver's door the rear wiper starts up, the tach drops
> to zero (no change in engine speed), the dash lights go off, the radio
> goes off, the top switches on the left (rear defroster and fog lights,
> I think) illuminate. If I turn off the headlights and then turn them
> back on everything goes back to normal. I think the engine may
> sometimes slow down and the dome light dim prematurely. Too many weird
> things to count.
> Just started acting up a day or so ago. Anyone suggest something I can
> check?

Earth points. Engine to chassis and chassis to battery earth straps.
Various other lighting circuit earth points and possibly fuse box earth
problems.

--
Paul ...
http://www.4x4prejudice.org/index.php
(8(!) Homer Rules ...
"A tosser is a tosser, no matter what mode of transport they're using."

So Gord Wedman was, like

> Here is a weird one:
> snip>
> Just started acting up a day or so ago. Anyone suggest something I can
> check?

Bad earth, or a lot of water somewhere it shouldn't be.

--

Rich

Pas d'elle yeux Rhone que nous

Check Grounds.


"Gord Wedman" <[email protected]> wrote in message
news:[email protected]...
> Here is a weird one:
> Engine running, headlights on, dash lights on, radio on, everything
> normal.
> If I open the driver's door the rear wiper starts up, the tach drops
> to zero (no change in engine speed), the dash lights go off, the radio
> goes off, the top switches on the left (rear defroster and fog lights,
> I think) illuminate. If I turn off the headlights and then turn them
> back on everything goes back to normal. I think the engine may
> sometimes slow down and the dome light dim prematurely. Too many weird
> things to count.
> Just started acting up a day or so ago. Anyone suggest something I can
> check?

"Gord Wedman" <[email protected]> wrote in message
news:[email protected]...
> Here is a weird one:
> Engine running, headlights on, dash lights on, radio on, everything
> normal.
> If I open the driver's door the rear wiper starts up, the tach drops
> to zero (no change in engine speed), the dash lights go off, the radio
> goes off, the top switches on the left (rear defroster and fog lights,
> I think) illuminate. If I turn off the headlights and then turn them
> back on everything goes back to normal. I think the engine may
> sometimes slow down and the dome light dim prematurely. Too many weird
> things to count.
> Just started acting up a day or so ago. Anyone suggest something I can
> check?
Thanks to everyone that replied to my query. I've been too busy to

investigate until yesterday. The solution is almost as bizarre as the

original problem.

I was able to locate 3 ground points on the vehicle. The battery cable

goes to a starter mounting bolt and from this bolt there is a braided cable

going to the frame. I was able to loosen the bolt at the frame, wiggle and

re-tighten. The starter mounting bolt was so difficult to reach I left it

for another day. The second ground point is a small braided strap under the

hood, near the windshield. Loosened both ends, wiggled and re-tightened.

The last ground point was behind the panel in the drivers footwell.

After all this work I was rewarded with no change. Same weird combination of

faults. In my original note I failed to mention a few other symptoms:

the cruise control would not engage if the headlights were on, the tach
would

go to zero and dome light dim quickly if lights were off.

Behind the drivers side footwell panel I happened to notice a rectangular
grey

junction block with pairs of black wires going into it. At one end there was
a jumper wire

that bridged the rows of connections. This wire was broken where it entered

the junction block. A rather strange break I must say as both ends were
almost

sheared off. Perhaps it got pinched against a sharp metal edge. I could not
pull out

the stub ends so I used 1/2 of a paper clip to re-make the connection. Lo
and behold

this fixed the problem!! Everything back to normal. I don't really know what
this

junction block does but I'm guessing it connects a bunch of ground wires
together.

So now you know that you should keep a few paper clips in your Land Rover
tool box.

Now if every fix could be so inexpensive.................