944 tach not working, help!!!!
 

I have a '84 944 and have installed 3 different tachometers, and none of them do anything! The car runs fine, but the MPG guage, shift indicator, and tach are non functional. The ground is good, and the back lights work. I have read through my haynes manual, and the wiring charts, but they are not much help here. I figure it's not getting positive voltage, but am not sure where to check for 12v on the plugs with my meter. Any help is appreciated!!!:eek:

Sounds like the wire that splits off of the DME harness is broken. Same wire that goes to the coil. Pin #1 on the DME connector. Think there is a small four pin connector in behind all of the instruments.

I may have a buyer for one of the tach's.

Cool, sounds good to me! I just paid $35.00 for the tach. Make me an offer if interested on that. Do you know much about the alarm? I just noticed a relay attached to the underside of the dash while I was poking around with my meter. I asumed due to the location, it was probably for the alarm, but have found no documentation on that. Thanks for the info, I'm going to have to dig around for that connector. Let you know how it goes!

Relays under the dash are usually not for the factory alarms. These relays are for the radio, power windows and AC stuff. Think I have a listing somewhere that labels them.

If you have an extra key hole just back of the drivers door handle then you have a factory alarm. The factory alarm grounds out the coil wire (could be the reason you tach does not work) and cuts the power to the DME relay so the fuel pump will not work. Usually the alarm unit has the necessary relays inside.

P.S. The electrical schematics for the early 944's and the early 924's are on the Pelican Parts side of this site.

Thanks, I went diging around first thing this morning, and found a two prong plug right of the DME that was unplugged. Everything works fine, now! Thanks a bunch! By the way, I have a temp/fuel guage spare as well as an oil pressure guage if anyone needs it! Thanks for the point in the right direction! I'll be back with more problems later, I'm sure.

Thanks for this thread, fixed my tach yesterday. Removed cluster, found tach was disconnected (2 prong connector), reconnected it and we're in business. Always like when it's something simple!