Stock Gauge Cluster Problem

[WQRed50]

I need some help in this, at least a good starting point....

I replaced the anti-slosh circuit, gauge faces and the bulbs in the gauge cluster. When I took it out, only the fuel gauge was inoperative. Now the temp, fuel and oil gauges do not work (speedo, tach, warning lights and volt meter works). The sending units do show voltage at the source, but in the dash, those circuits are dead.

I read the voltages at the two plugs in the back of the dash (with and without the ignition on) and they are dead.

The moron who owned the car before me has at least two alarms and wiring from the radio clogging the under side of the dash which makes it tough to track anything down. I just need a clue for something to look for.

Any ideas from the electrical gurus out there?
Thanks!

 

[Saleen0679]

Judging by your three gauge symptom it sounds like you may have lost your IVR (Instrument Voltage Regulator). The regulator controls the voltage to those three gauges. I'm not sure what Ford is using now, but the IVR used to be a rectangular can shaped unit connected to the back of the cluster on the right side. It was snap/screwed in to the flex cable.

 

[HISSIN50]

do 90's have IVR's?

 

[Saleen0679]

do 90's have IVR's?

That, I'm not too sure about. I know that stangs had them at least up to '88 as far as my documentation goes. The symptoms were the same as an IVR failure. I figured it was worth a look.

 

[HISSIN50]

I hear ya bud - I just was not sure. Something was telling me that IVR's stopped around the time that air bags started popping up (circa '90 model year). I know 88's have IVR's and I am really pretty sure that 89's do too. Not real sure after that.

(I was not nit picking with you at all; we both try to be savvy and know exactly what years had what - I really don't know).

 

[Saleen0679]

(I was not nit picking with you at all; we both try to be savvy and know exactly what years had what - I really don't know).

Never took it that way at all. You made a very valid point since Ford made some substantial electrical changes between the 87-89 and 90-93 model years. I think that can unit has been back there for a good thirty years. It's past due for a change.

My searching hasn't some up with much. I've seen someone mention that the IVR changed between 89 to 90 and also that the unit went from a can type to a small green circuit board, but I haven't been able to verify any of the information. Hopefully someone with concrete info can chime in.

 

[WQRed50]

Thans for the replies, but I will have to track this module down. I do not recall seeing anything like that om the cluster. I will track down the right side wiring and see if anything like that is there.

I hope this is attached, the back of the instrument cluster