dashboard lights

[chrisdbr]

dashboard lights flash when windscreen wiper is on or side lights turn on.Also clock reverts to zero.
c220 1994 model-never had any problems before-engine does not stall or miss when this happens which is intermittant when the wiper is on .i.e will not flash or clock return to zero as long as you dont touch the light control or the windscreen wiper control

 

[television]

dashboard lights flash when windscreen wiper is on or side lights turn on.Also clock reverts to zero.
c220 1994 model-never had any problems before-engine does not stall or miss when this happens which is intermittant when the wiper is on .i.e will not flash or clock return to zero as long as you dont touch the light control or the windscreen wiper control

Sounds like a poor ground cable some where under the dash

malcolm

 

[chrisdbr]

Thanks malcolm-can you explain a bit more as not saw what a ground cable is or looks like.
If you can point me in the right direction it would be very much appreciated
Chris

 

[television]

Thanks malcolm-can you explain a bit more as not saw what a ground cable is or looks like.
If you can point me in the right direction it would be very much appreciated
Chris

All electrical devices require a + and - to operate, On our cars the - is what we call ground, and the + is live and fed from the 12 volt supply. to save wieght and cost many circuits use a common ground, if this connection becomes poor strange things can happen when you operate something and it interacts with something else. not always easy to find, and of coarse it may not be that, its only by removing the under dash cover and gently move the cables to make the fault appear.

malcolm

 

[chrisdbr]

thanks Malcolm-when it stops raining i'll give it a go.I recently had to replace the ventilation fan because the motor failed due to it getting wet when someone washed the car using a power jet ;but thats on the other side.
Chris

 

[C220GJS]

The ground or earthing point for your dash panel is a stud on the bulkhead behind the instrument panel ,you will have to remove the instrument panel for access and you will see all the brown wires going to a common point.

 

[chrisdbr]

this is bringing back my youth!nice day at the moment so removed housing and looked at the wire looms .Did not take out dashboard as didnt know whether to push or to pull.I noticed a brown wire going to earth next to the brake release handle which looked okay and there are also quite a few in the engine compartment just in front of the fuse box which also look okay.Just a bit more info the lights flash and the clock resets to zero when i operate the side light swith or the wipwer switch.It will not flash after the first operation.ie if i repeatedly operate the switch there is no further flash and i wonder if it relates to the clock somehow/;also the only other switch which causes the problem is the hazard warning light switch-which when operated
causes the clock to go tyo zero and the the dash board to flash on and off with dials moving in time with the hazard warning lights.Any further advice please-how do i remove dashboard and should all the dashboard light up when in hazard warning mode
Chris

 

[C220GJS]

Symptoms definitely sound like a poor earth as Malcolm says.

 

[chrisdbr]

thank you-how does the dashboard come out please ?
Chris

 

[C220GJS]

This link has a section on removing the instrument panel, along with other useful things. http://202tech.mkosonen.com/howtos.html . Make sure you disconnect the battery or keep the ignition off while the instrument panel is out or your will trigger the SRS light.
Geo.

 

[chrisdbr]

read it and went out to car and the wife had taken it shopping-lets hope I can get it out without removing the steering wheel
Thank you all for all your help
Chris

 

[chrisdbr]

The aa man came as other car wouldnt start but unable to help with this problem,Steering wheel has no position changer so propose to take it off tomorrow and then ease out the dashboard

 

[bitonw]

Sounds like a battery problem... low voltage or deing...

 

[C220GJS]

The instument panel will come out without taking off the steering wheel, just a bit awkward to release the wiring catches but have done mine three times without removing the wheel and no damage.
Geo.

 

[chrisdbr]

gentlemen thanks for responding-did a long reply which seems to have got lost so did your merc have an adjustable steering wheel as mine hasnt.Will have a go if this is the case but chickend out after getting the housing off as I thought taking steering off looked too scary.Interested in the low battery-always had a prob with it loosing its charge.some have said its because of the cobra alarm which we no longer use?c220 1994 model earth points I've didcoverd look solid

Chris

 

[chrisdbr]

Another quickie what about the clock this looks a bit suspicious is there anyway of eliminating it from the equation as I cant see a separate fuse for it
Chris

 

[chrisdbr]

Sorry just looked up deing...on google and it doesnt come up with anything which sounds electriclal so love to know what it means.prepared to buy a volt meter if necessary
thanks
chris

 

[C220GJS]

My car has a non-adjustable steering wheel like your's.

 

[Fandango]

Chris, with your level of mechanical knowledge it's best left to the professionals.

Bitonw simply made a typo, he meant it could be the battery dying.

Sorry I don't have anything more constructive to add. Good luck with getting it sorted.

Regards

 

[bitonw]

Sorry just looked up deing...on google and it doesnt come up with anything which sounds electriclal so love to know what it means.prepared to buy a volt meter if necessary
thanks
chris

Oh, sorry I mean dying... :Oops: (I'm not British so I make typo's).

I had this kind of problems with a Renault 25 Turbo Diesel years ago. All meters want up and down. Even the speedo when not even driving. It was the battery who was dying. When I installed a new battery all was fine! :-D

Put your car battery on the charger for a night and try it again to see if you have change.