I have managed to loose the speedo, tach, fuel gauge, radio, and heater controls.
Started with the body control module. does not seem to be the problem.
All fuses are good. Totally lost as to where to go next. Can't find any schematics on line.
Next step might be a fire and marshmallow roast.
Options please.

 

Not having a schematic to look at.....I think all of these are powered through the ignition switch. The large switch that is on the steering column, not the key tumbler. Maybe just loose...hopefully...

Have to remove the trim panels to get an eye on it and then hope your back is in good condition......

 

Those items do not have a common power circuit but they do have a common ground circuit. There are other items on that ground circuit that are not malfunctioning so its not likely the ground connection to the body. There is a splice pack (SP203) which is near the ashtray where these common items combine their grounds before heading to the frame attachment point (G201) at the right side of the dash. Multiple power failures or multiple component failures cannot be ruled out either. If it were me I would test in the order of the least amount of dash disassembly first:

1) Use the radio to find out if its power, ground or the radio since your going into the dash anyhow and I think its relatively easy to remove. Get to the connector and probe from power on the connector to chassis ground and then known good power to connector ground.

2) If its the ground then inspect SP203 and ground point G201. If its power and you have already checked the fuse then you have a wiring problem from the fuse box to the radio that is not in common with the other items. If so then I can give you more guidance.

3) If ground and power are good then its the radio and a coincidence so we move on to the other items, probably the climate controls because you are there at this point. Let me know.

BTW, I don't like marshmallows but I do like chasing down tough failures so don't roast the truck on my account. LOL.


George

 

George,
All good info. I looked at your suggestions. Sadly to no avail.
Finally I found no power on the gauge connector "A10".
"B3" had a good solid ground. >3 ohms.
So I followed the power loss. READY? Holding the marshmallows for you.
The wire coming off the output side of Fues 15 was broken on the inside fuse block.
This vehicle is the dog running car. It lives off road. I suspect I'll see more of this eventually.
So with a tip of my hat. I thank you guys for inspiring me to continue the struggle.
Saved me a fire sale.

Best Regards,
Squidly,