Guage fuse

[mcp1810]

Today while driving my guage fuse blew. When I put a new one in and turned key to cycle glow plugs I had lights for about half a second, then fuse blew. When I turn headlights on I get the lights on warning tone. the fuse I am talking about is a 20 amp on the block under the dash. Truck is a 94 K2500 suburban. Any ideas?

[BobND]

I don't have my manuals with me, but as a wild guess, bad alternator or fuel heater?

[mcp1810]

My first thought was alternator, I pulled it and took it back to NAPA. They bench tested it twice and said it is fine. I have also since discovered that it is not charging on the truck. I have already ruled out the switches on the dash board and anything beyond them. I HATE ELECTRICAL BUGS!!!!! :mad:

[MTTwister]

Any fusible links?

and of course - corroded bat terminals? Check the Grounds?
I hate tracking this kinda stuff down too. Good luck!

[mbrew]

I don't have a schematic handy but based on past experience the 2 pole temperature sender can radomly go to ground and blow the gauge fuse. I had a 4.3 Olds V6 diesel that drove me nuts trying to find the source of the heartache. (my wife's car of course)
Good Luck

[HowieE]

JeffMd

Lets have a little more detail. Can you give us the fuse Number from the terminal block. If not is it the instrument panel lights that are going out or the instruments themselves.

You say a 20 amp fuse. If the panel lights are going out and it is a 20 amp fuse the parking lights should also be out.

Let us know.

[mcp1810]

I finally found my manuals and have a schematic to work with now! :D The fuse in question was for the gauges themselves not the dask lights. I want to say it is slot 32, its the top left of the fuse block. I had already pulled the instrument cluster, and the low coolant sensor and temp sensor leads but fuse still blew. From looking at the manual I think it might be either the cruise control switch or module. I also bought some test equipment (easier than finding my old stuff) and hope to resolve this today!
Thanks for the help, I hope to have good news soon! smile.gif

[radrecon69]

I had the same problem it didn't blow all summer and soon as it got cool it blew my dash fuse. Found out it was the fuel heater disconnected it and haven't blowen a fuse since.


Rick

[mcp1810]

And the winner is..........


FUEL HEATER!!!

Which of course I didn't see listed as being on that fuse anywhere except here and on the schematic with a whole bunch of other stuff.
Thank you all for your help! smile.gif