Hey all, I am new to the forums. I have a 1988 F150 XLT Lariat 4x4 with the 5.0. I have been pulling my hair out trying to figure out why my gauge cluster is not working. I have tried to buy another one from a salvage yard but still have the same issues. Speedometer, lights, and turn signals work but thats it. 4x4 indicator does not work, and Volt, Temp, Oil, pressure all do not work. I have replaced all of the sending units that I could, I dont know where to go from here. Any help would be greatly appreciated

 

Welcome to the site!

For the 4x4 indicator - suggest to check the bulb.

For the instrument cluster - FWIW I had problems with erratic gauge readings, found the problem to be the connection between the plug and that flexible circuit film thingie on the back of the cluster. A little bending and reseating of the plug seemed to line things out.

Hope this helps, keep us posted.

 

Replaced the buld. No change. Tried that already with the plug and circuit board still same thing.

 

You could need new temperature and oil sender sensor. As for everything else, have you checked fuses?

 

Same thing happened to me, and it was just a blown fuse. Got in it, started her up and noticed none of my gauges but the speedometer were working. I'd definitely check all your fuses before I went and bought more stuff for it!

 

Let me give a bit more background, this is my dads truck, he bought it new back in 1988, he used it for 20+ years as a work vehicle for his grading business, it carried a diesel fuel tank in the bed up until about 5 years ago when he parked it. Hes getting older now and I have always loved this truck and have decided to restore it. I checked all of the fuses, all of them are good. I think I may have found the problem though. While i was tracing down wires trying to find a short I found 3 wires on the interior main pigtail that were melted together, I also found the Idle Air Control valve wiring was backwards as was the temp sending unit wiring. There were several other cuts made in the engine wiring harness, so I have decided to replace it. I will let you all know if this works!!

 

Hope it works man!