tacho not working

King_Jut · Post by **King_Jut** » Tue May 10, 2005 10:19 am

Hi all....forgot to put this on the last post....

My tacho dont work...it did work but it jumped around....maybe lose connection...is there anywhere i can get a wireing plan for the Car/Tacho..also now when i hit the main beam....the dash light for the tacho goes out...?? bad earth...???

Barry · Post by **Barry** » Tue May 10, 2005 3:51 pm

If its the same as the earlier (73 ish) 911's then check the feed wire on the actual tacho (centre one on mine, between the power (red/black) and earth (brown). If this is O.K. then check the feed up at the other end: you still run points? I wanted to disconnect mine, and initially just unplugged the feed: sure enough the tacho jumped all over.

Has anything else on the car been changed? Points, ignition unit, engine been out: all that sort of thing.

Anyway, if mine was anything to go by, its as likely as not, not to be the tacho itself so much as feed. Then again, yours might be completely different, in which case ignore all of the above ...

Barry · Post by **Barry** » Tue May 10, 2005 3:55 pm

Forgot to say, if all looks O.K., might be worth disconnecting tacho feed at engine and tacho, and run a meter down that whole circuit: i.e. put a tempory wire onto the female terminal that would normally connect to the tacho feed, run it right back to the engine bay, and touch your ohmeter between that wire and the tacho feed wire from the engine (now also disconnected). If all is well you should see a near zero resistance reading.