1998 GMC 3500HD Dual tank issue.

My fuel guage stops working, and I look under the hood - IGN-E fuse is blown. I checked the AC Compressor, and it's not shorted, and it's not got an aux fan. Only things listed in the manual were Aux fan, AC Compressor clutch, hot fuel module, and dual tanks. There is what looks like a small electrical pump between the two tanks that is pretty rusty. Could that be the cause of my short? I've never worked on these dual tanks before, so I don't know. Thanks for looking!!

Hi. I have a 1996 3500HD w/ dual tanks. My gauge quit the other day too. After much messing around, I discovered a balance module that had a corroded curcuit board. I resoldered a terminal or so, and that fixed it. If you look under your truck, I beleive it's in front of your front tank there is a bracket bolted to the inside of the frame rail that has a 4 inch by 4 inch by 1 inch black box on it. That is your balance module. Let me know if you need any help!

[email protected],
Thanks for your response - I checked the module, and it looks like brand new inside - no corrosion. I'm going to replace that transfer pump and see what happens - it looks gawd awfully rusty - as it's a plow truck. I think it's seized. I'll bench test it off the truck, I don't want a fire!!!

Well, I replaced that "transfer pump" between the tanks, and the fuse is still good - fuel guage works. Bench testing the unit showed that it drew anywhere between 4-15 amps - which would indicate the overload on that circuit.