I have a 1994 4runner and it keeps blowing fuse for gauges when I put it in reverse

You have to isolate the wiring harness that goes to the reverse light.

Somewhere in that path a chafed or bare wire is grounding out and blowing your fuse when you put the car in reverse.

You need to take the car to an Auto Electrician. This is a clear case of a stripped positive + wire making contact with the body of the car thus shorting out the fuse. Do not attempt to put in a higher amp fuse to try and resolve the matter. The fact that the fuse blows if a safety measure that prevents the car's wiring system from completely burning out. Save yourself this headache and take the car for an electrical system test. Explain to the Auto Electrician that this happens when you put the car in reverse - and he my have to completely rewire the reverse light and reverse switch in the gearbox.

You can check the reverse light bulbs and see if they are bad/corroded, also check ground wire.

You probably have a wiring short, and unless you know your way around under the dash, you'd do better taking it to a repair shop that has an employee very knowledgeable specifically in electronic gauge troubleshooting and repair. Save yoursef the time and grief.

Check for a princh wire some where on the wireing harness that hooks up to the sending unit on the tank, Or a break in a wire, Or evan bare wires, if you don,t find any of that stuff ,There is a problem with the sending unit on the tank. But to me it sounds like a problem with one of the wires going to it.

id say you have a chaffed wire in your harness somewhere if you dont engage reverse at all while driving. check your wiring harness with an amp gauge.

maybe its the board holding the fuses faulty

hi
check the wire because if the fuse keep blowing there's a wire somewhere on the car that has contact with the frame so everytime you put your car on reverse the 12V wire shortcut on the frame so the fuse blow check all your positive wire and your bulb as well
Good luck

Your 20 amp fuse will not blow if glowplug wire shorts. each plug draws 15 amps which is 120 amps total.I think there are in line fuses for them. Try to wring out where each output from the fuse goes, disconnect all and reconnect one at a time till it blows.That should point to your problem process of illumination! Good Luck!!

7.5A fuse keeps blowing because there is an electrical connection fault. Take the car for diagnosis.