Tach Out

[520i]

Hi, i have a 90 520i with a little over 60k miles. Recently i noticed that the tachometer stopped workin, dropped to 0rpm and also the fuel consumption needle isnt workin as well. The inspection light is goin off but havent had time to take it to the shop and wont have any time for a while. The car runs great other than the tach and fuel consumption gage not workin. Before it completely gave out, it would ocasionally come on and then drop back to 0 and now hasnt moved for a couple of weeks. I am wondering if it might be a lose wire or something similar because just a visit to the shop to figure out what hte problem is will be costly. Any ideas greatly appreciated. Thanks.

[doogie]

I've got an 89 520i (although it has 145k on it!)

The tach problem is either due to faulty batteries on the SI board or faulty capacitors. I've got the same problem, pulled the cluster and found that one of the batteries was totally dead, I've ended up running some wires from the points on the board to an external battery connector with new nicads in it, but I'm still having problems (at the moment if I disconnect the car battery, reconnect and start the engine, the tach works until I switch the engine off, then it doesn't work again till I next d/c the battery!) - I don't know wether it's dodgy wiring/ soldering or whether I need to do the capacitors as well.

[CiscoKid]

does the cluster lights and spedo worK?

[520i]

ok thanks for yalls help so far. The speedo and all the lights work in the dash, even the tach lights. I will try disconnecting the battery and the firin it up and see if it comes on.