vdo tach stopped working

[mnovelli01]

I have a 2004 8.1 crusader engines and my starboard tach stopped working.First it fluctuated wildly now stays on zero.I removed and cleaned wiring terminals on tach,no help,swaped tach with port engine and tach worked.Now I'd like to check wiring on engine but I'm not sure if tach wire goes to alternator or ecm.Have not checked volt output to tach yet.Hoping its just a bad contact or ground .Anyone with similar problems? thanks.

[Head_Shaker]

Did you read this post: https://www.tiaraownersclub.com/forum/sh...p?tid=6235

Also these can be connected to your ecm, distributor or alternator depending upon your setup.

[AyeCandy]

I had a similar problem with my VDO tachs from my 2007 Tiara 3600.  Was told it could have been a problem with the ECM, but thought it was strange it started happening with bothering the port and starboard engines.  I ended up sending to Fort Lauderdale Tachometer for bench testing, they could not find a definite problem but ended up replacing an LCD hour display and "reflashed" the tachs(whatever that means).  Got them back within 14 days and installed them and they have been working great.  Sure better than trying to find a new compatible tach and then not have it match the other gauges on the dash.  Nope that belps!