Hello All, I am new here. I just purchased the van from my boss who was some what vague on the details. All he could remember was that the Fuel hand did not work. And the Owner before him had to put tape over top of one of the door connections (in this case it is the back left door the one with the spare on it) because every time the door was opened it would blow a fuse.

Now, that I have the van, I can tell it isn't just the fuel hand, it is everything except the speedo.

I was wondering if someone here has a wiring diagram for the gauge cluster, as I suspect it either isn't getting power, or ground or both. I have searched for about 2 hours and have come up empty handed. Or if someone has any more troubleshooting techniques I could try that would be very helpful as well.

Info on the Van:

1987 E-150 Conversion
5.0l Auto trans

Thank you,
Andy

 

Here we are.

 

A few seconds looking at that diagram tells me you should go cruise on over to the CLUSTER voltage regulator and assault it with a multimeter to see whassup there. Check that you are gettting 12v on the gray-yellow wire when the ignition is on, then measure after it to see if you are getting anything on the other side. You should get 5-ish volts there.

EDIT: Clarified which VRU i was referring to.

 

does ANYTHING in the cluster work other than the speedo (illumination, indicator lamps, etc)? if not, maybe its unplugged.
if the illumination lamps work, but indicator lights are still dead, you likely have a problem getting power from the ignition switch to the cluster.

the speedo is entirely mechanical, so it makes sense that it isn't affected by your problem

 

The diagram shows that the cluster grounds the indicator lights, not supplying power to them. That is handled by the indicator/turnsignal/hazard switch. This cluster is pretty much devoid of idiot lights if it follows this diagram. If the cluster is 100% dead, then yeah take it out and check the cluster's connector to ensure it hasn't gone for a walk and popped out.

The other thing about older vehicles like this (I learned this from owning a 1964 IH scout) is the Previous Owner (AKA PO Virus) may have done some inexplicable, awful things to the wiring. Who knows what may be found behind the cluster...

 

Thanks alot for the diagram and the advice. Unfortunately my multimeter is in the back of my car and it is in the shop, and wont be out till monday after next. So this monday I will borrow my bosses so I can start diagnosing this thing. I know that my boss never did anything to the wiring, he would always take it to his mechanic for any problems, but he nor the mechanic ever tried to figure out why the gauges didn't work. But, now as to what the PO before my Boss may have done.. that I have no idea.

As far as the other questions, It illuminates fine, and the signals work fine, Im unsure of other lights as I didn't pay much attention. I haven't looked to see yet if the Hi beam indicator works.

 

then for that we know that the cluster is connected to its wire harness, and appears to be properly grounded. the lack of other gages indicates that either they aren't recieving power from the ignition switch, or possibly the IVR (instrument voltage regulator) is bad, though usually those fail in such a way as to have the gages reading high. your mulitmeter or even a simple test light will show you whats up

 

Im going to start trying to track it down on Monday afternoon. Thanks for the information.

 

And also, today I found out that the Parking Brake light works, and the Hi-Beam indicator works.

 

A small update. Using a test light, i was able to determine that there was No power going to the voltage regulator. I traced the lead back to the connector. On the connector there were two wires running into where there should have been power, one of them was yellow/gray, don't remember the other right off hand. Neither wire had power, I was unable to trace where these wires go. My brother was under the hood looking, he found a push in connector at the battery that wasn't pushed in, he locked it in, and the voltage meter started working. I wired a fused wire to the voltage regulator and now all of the guages work, except the fuel hand. You can tell the fuel hand works, because it comes up and stops dead on E, so, an educated guess tells me it needs new floats in the tanks.

Thanks a Ton for the Diagram!