Tach not working?

[unioncreek]

I've seen post on the forum about the tach not working. Mine has worked most of the time since I bought it in the last year. But occasionally it would not work so I would just tap on the dash to get it working. Lately I have to hit the dash harder and sometimes that doesn't work. I heard talk about there being a short in the instrument panel, but not the location if the is one definitive one. If you have had this problem can you list where it was and if you have a pict of it, it would be greatly appreciated.

I have the 1998 4.0 SOHC XLT.

Thanks,

Bob

 

[XLTrunner]

Following this too, as mine does the same thing; although usually just on cold winter days. Since I rarely drive it in the winter, it hasn't been enough of an issue to bother removing the cluster as of yet.

 

[Deleted member 352605]

my speedo and odo sometimes dont work... only when its hot tho... I'm thinking if its in cold weather, condensation could build up and cause a short because waters a good conductor of electricity... so I'm thinking maybe check wires close together

 

[MrQ]

It's probably a cracked solder joint. Thermal expansion and contraction can break those connections and cause issues like this.

 

[donalds]

It's probably a cracked solder joint. Thermal expansion and contraction can break those connections and cause issues like this.

That's what happened to mine removed the cluster and had her fixed up in just a few minutes I I hit the rest of the joints on the back of that gauge to

 

[Kevin Hawkins]

I've seen post on the forum about the tach not working. Mine has worked most of the time since I bought it in the last year. But occasionally it would not work so I would just tap on the dash to get it working. Lately I have to hit the dash harder and sometimes that doesn't work. I heard talk about there being a short in the instrument panel, but not the location if the is one definitive one. If you have had this problem can you list where it was and if you have a pict of it, it would be greatly appreciated.

I have the 1998 4.0 SOHC XLT.

Thanks,

Bob

I had a 98 up until lately and never had an issue. I sold it with 236k on it. I bought a 97 5.0 and have to smack the cluster often to get the tach to work. I haven't tore into it yet but is coming... I can't stand for something not to work as it should.

 

[410Fortune]

This is what the speedo and tach modules look like inside the cluster

The modules are pressed into the cluster housing when re assembled, the “pegs” that make contact when you press them in… well they need to be clean and the modules need to be pressed firmly or you can get intermittent speedo and tach issues

Over the years I have had to replace a couple of speedometer drivers and a handful of tach drivers.. in addition to having potential solder joint issues, condensation issues they also wear out with time.

I have a two big boxes of clusters and cluster parts if anyone needs parts

 

[Motorhogman]

Funny this came up.. Every now and then the tach needle on my 2000 Sport drops down to 0 when it's idling. Tap the cluster glass and it moves back up. Just started doing this a couple of months ago. Least that's when I noticed it. Thanks for the info on repairing it..