I have a 1994 Bronco and sudenly it is eating speedometers. I drove it one day last month, and everything was normal, then after sitting an hour, the speedo was dead, no display in the odometer, and the fuse was blown. naturally the transmission shifted very hard, etc. (E40D) I replaced the cluster, and aside from losing 30,000 miles on the readout, the fuse was OK, and the trans worked normally. now today, it is being used by a friend, and apparently it had done it again. I am out of clusters, what is causing this? How do I fix it, can I fix the original cluster?

 

I would guess that there is a short somewhere, possibly a pinched or bare wire. I am interested to know the solution to this.

 

a 30 yr ford tech who now runs his own shop, and the service manager at the local ford dealer think its a fluke, so I will go get a cluster tomorrow and find out. Will keep you posted. Bronco has had no wiring issues until now,and no modifications. Now I find out the cruise and horn are not working either. Hmmm.

 

will be popping in the next cluster tomorrow. anyone have idea about the cruise and horn? no blown fuses, and never did this before. stumped.

 

The Speed Control (cruise?) will not work if the PSOM is bad.
The PSOM sends information to the Speed Control, PCM Computer, Speedometer and the Odometer.
You can replace the PSOM instead of the whole cluster to get the Speedometer working again.

Horn and Speed Control not working together most of the time is a bad clock spring but could be separate in your case.

 

the new cluster is from a 92, and the check engine light comes on while the other dont, pulled the cluster to look closer, then remembered the fuse that blows when it goes out. put in new fuse, but fuse blows even if cluster isn't plugged in, so wiring issue somewhere. I ordered a new clock spring from ford (cheaper than even my employee discount at work) does this circuit go through the column? I am going to look tomorrow, just hoping someone will know.

 

Does what circuit go through the column?

 

I'll have to go look, but its a 10 amp fuse that feeds the cluster. fuse 18.

looks like it does, according to the fuse panel, electronic shift module 4x4,speedometer, air bag restraint automatic transmission shift interlock (which works with fuse blown!!??) automatic day/night mirror.

hopefully the wiring in the column is ok, but we will see when it comes apart.

 

The only item in your list that would use #18 in the column is the shift lock.
The shift lock is on the bottom of the column about half way up.
The circuit that fuse #18 feeds is #296 the all of its wires of this circuit are White with a Purple stripe.

 

It wasn't the clock spring ($50), it isn't the steering wheel, unplugged the speed control unit, that wasn't it. circuit 18 is a 10 amp fuse, manual says it controls air bag restraint (along with #5) day/night mirror, auto trans shift interlock,electronic shift module 4x4 overhead console (does not have one) and speedometer. does the white/purple wire go directly to the shift interlock? I can see almost the entire run, but I could cut/splice around.

 

so what will keep the speedo, cruise and horn from working? and blow #18? I guess I will have to unravel the harness between the fusebox, the cluster and column...

 

FOUND IT!

the white with purple wire splits off within the harness to a few different locations. one of them is the auto-dimming rear view mirror. while it was un-plugged, the fuse would still blow, but while tracing out all the wires, I found that the white/purple wire that feeds the mirror was rubbing on the window trim. Fixed that, and now everything works. now I have two extra clusters, including a 1992 one that may be able to reprogram more than 6 times. so it wasn't a total loss.

This isn't a daily driver, so I wasn't frantic to fix it, it gets used sparingly in the summer, but daily in the winter, but it sure was nice to finally get it fixed. this little Bronco has been good to me, lived through my oldest son's four years of college (100k miles) and even with rusty wheelwells, I usually get offers matching what I paid for it 6 yrs ago... next year, paint and rust repair...