Greetings,

As of last week, I'm experiencing a new problem on my '95 850 T5 wagon (manual box).

It's okay setting off around normal roads, but after about 5-10 minutes on the motorway, the dash panel instruments are going mad: they seem to be flicking between working and non-working states quite rapidly, e.g. the speedo will try to climb to real speed (80mph or so) but then drop back down to zero.

Instruments affected are:
speedo
rev counter
LCD computer (all 6 functions - either has clock only or flashes madly)
temperature gauge
petrol gauge
milometer & tripmeter

The only instruments not affected are the turbo boost gauge and the LCD clock. In all other respects the car functions normally (drives fine, lights all work etc).

I wondered about either a relay problem (the Haynes manual isn't very helpful about relays) or a loose wiring connection or short, but have no idea which it would be.

Any thoughts ???

Regards.

Nick Pitfield.

I've seen dash stuff go whacko from a weak battery.

Ignition switch.

Weak Battery ? the original battery completely died on me in a town centre car park in early 1999 - I replaced it with a high-quality Halfords (re-badged Exide) battery after recommendation by the AA patrolman. On the basis that batteries last about 3-4 years it could be about due to fail, although all the rest of the electricals seem fine, it starts fine and there's no battery/charging warning lights showing. Will consider this though...

Ignition Switch ? I would have thought this would have affected more than just the dash instruments ??? Somebody once told me not to have a heavy keyring etc with my car keys (this was after problems with a non-Volvo) - I was quite sceptical at the time. I do have to admit I have about 12-15 keys (some of them quite big/heavy) and a quite large Wenger swiss army knife on my keyring: could this really cause such a problem ???

In the absence of further ideas I''l start by checking the battery condition and connections...

Regards.

Nick Pitfield.

"Number of keys has nothing to do with failure of the key switch.".....well I do not subscribe to this theory. I think the amount of excess crap on the key ring will eventully have a effect on the switch. IMHO I think its best to just keep ONE key and the fob hanging from this prone to fail switch.

Another thing I would check is the battery connections....be very sure that are clean and tight!
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Steve F. in Hoboken, NJ

Steve,

Sorry for lateness of reply...

You were spot on - one of the battery connections (not the chunky big wires but one of the smaller ones) was loose. I suspect this was just rattling around on the bolt more at speed making the connection worse and worse. Tightened it up and all's working again :-)

I think this may have happened last time the main dealer had her - I had them fit a new manual tranny reversing light switch (didn't have the time or deep socket to do it myself) and I suspect they may have disconnected the battery during this replacement.

Regards.

Nick Pitfield.

Number of keys has nothing to do with failure of the key switch.

And the symptoms you describe are classic 850 ignition switch failure symptoms.

Lousy electrical components have everything to do with this problem.

From your spelling and writing style, I'd say you're from the UK?

If so, to put this in perspective, and considering its reliability, the 850 ignition switch may have been originally designed by Lucas.

Good luck.