1475glenave

i recently replaced a 15 amp fuse in 1985 corvette that supplies radio antennae, under hood lights and several courtesy lights. all these functioned immediately after replacing fuse but when i turn the engine off then restart the car the fuse BLOWS and blows again after replacement . what could be causing this and how to correct?

thanks

Cjunkie

Put a 20 amp in there

1475glenave

thanks for your suggestion. is there a liklihood of damage to any of the components that the fuse and circuit supply by putting in a higher amperage than is recommended?

Aerovette

Put this in, watch for smoke and you'll locate the problem.

PatternDayTrader

You have a short somewhere. Make sure there's not a coin in the cigarette lighter socket, that happens a lot. Don't put larger fuses in it unless you want to find the problem by seeing where the fire starts.

1475glenave

should i remove the car from my garage first or can i leave it and just have a fire extinguisher close by?

1475glenave

thanks for your response...no coin and the last thing i would do is put in a larger fuse. a trip to my mechanic is probably in order.

jetskibruce

Is the radio on? Meaning is the antenna trying to go up? Make sure the radio is off, then start removing courtesy lightbulbs. An buy a bulk pack of 15 amp for the testing, or your mechanic will need to. To save fuses, if you have an ohm meter, with the fuse out check the ohms to ground in where the fuse supplies the power, disconnecting the battery first to protect the meter. They you look for the low ohm circuit which is the current draw.

Hot Rod Roy

The circuit for this 15 A. CTSY CLK fuse is quite complex. Let's take one step at a time. Try this: Turn on your ignition, but don't start the engine. Turn off your radio, and leave it off. Do you hear any noise from the antenna motor? Does the fuse blow?

Do you have the FSM (Factory Shop Manual) for your '85?

I built a test gadget to help chase blowing fuse problems. Using an old, but good headlight, I wired a bad fuse as a plug for the headlight. Plug this into the offending fuse location. If there's no problem, the light will be dark, and the accessories will work. If there is a problem, the light will shine, but nothing will smoke! Then you can disconnect the stuff shown in your FSM that's on the same circuit until the light goes out. The next most likely culprit is your courtesy light timer.



Using an ohm meter to find a short can be tricky. If you aren't real good with electricity, you could burn up your ohm meter!

jetskibruce

light bulb idea is ok for shorted circuits if the bulb stays under 15 amps and is not shorted.

I don't think he would burn up a meter with the battery disconnected.

I think a cheap led courtesy bulb backwards might blow the fuse.

hcbph

What about getting a 15 amp circuit breaker for doing the testing? it would trip like a fuse but should be able to be reset either by turning off the switch/circuit and possibly save some $$ while tracking the problem down.

Hot Rod Roy

The bulb trick would only be for a short time to indicate that you have a problem. You would not leave the light on for long enough to overheat the wiring!
I x E = P
15 A x 12 v = 180 watts
Bruce, you're right! Don't use an aircraft landing light!

Have you ever tried installing an LED backwards? How do you think a "diode" works?

1475glenave

thanks i wish you were my neighbor to help me...you are very knowledgeable...too far above my pay grade so i think i will be taking it to my mechanic...thanks again

1475glenave

thanks for your expertise but i am afraid this job is too far above my pay gradeoff to the mechanic...thanks

billschroeder5842

A man needs to know his limitations. Good luck!

1475glenave

thanks bill