Car: 1984 635 CSI, manual gearbox.

I was returning the tachometer to zero and both the speedo and the fuel economy gauges simultaneously stopped working.  The gauges are electronic.  I have replaced the speed sensor and as far as possible checked out the units and can see no faults - no visible breaks in the PCBs.  All fuses in fuse box are OK - HELP PLEASE - anybody come across this problem before?

Tony

01366 500945

e-mail: mailto:Kstainedglass@aol.com">Kstainedglass@aol.com

Hi,

   I have got a 1984 628 which I had a similar problem with the speedo not working.  It was caused by the batteries on the circuit board leaking and damaging the circuit board.  Had to get a new one which was costly.  You can always try getting a second hand VDU out of another 6 or 5 E26 or even a 7 E23, just look at your local scrap yard.  I seem to be collecting VDUs ,if i'm at a scrap yard and a see one I buy it just in case it happens again.

Dave

Hello,

I have a similar problem with my 1986 635, but my Rev counter and Temp Gauge are affected.  Assuming I can track down a board what is involved in fitting, i dont seem to be able to find anyone who sells a tech manual for the six series (any ideas on this too!).  While i was there i wanted to change a bulb in the dash thats blown.

Also, i have heard you can change the batteries if the board is undamaged, is this practical?

Appreciate any help.......

Hi All,

My 1985 CSI developed the speedo and fuel economy fault immediately after having the air conditioning regassed.  Air con guy said it was nothing to do with him but I suspected he had loosened a connection somewhere.

The speedo does not work at all but the economy meter sits at zero and every so often swings all the way left and then drops back to zero again.  Service lights very occassionally all go green and then go out again.  Rev counter and other dials are not affected.

I have checked the wires under the dash but I have not removed the instruments yet.

This is a common fault on sixes and is easily fixed if you know what you are doing. The screw i mentioned earlier is plastic. Don't buy a second hand board as it may be no better, just get the old one fixed. Hartlake charged me almost nothing for the work. But I am a regular customer. Maximum cost £40.

PTAOTNY wrote: Car: 1984 635 CSI, manual gearbox

I have a manual 6 too, very rare . What colour is it? and whats the spec? If you are free this weekend there will be a group of 6 series owners meeting up at the New Inn in Heckfield. Last meet we had 26 6's and 39 cars. This offer is open to anybody. look at the heckfield photos on the front page to see some of the cars.