1995 Jeep Grand Cherokee what have I done?

Tiny
REDROCK99
  • MEMBER
  • 1995 JEEP GRAND CHEROKEE
  • 5.2L
  • V8
  • 4WD
  • AUTOMATIC
  • 193,000 MILES
I put a 25 amp fuse where a 15 amp fuse should have been, and now I am suffering the consequences. I knew I shouldn't have done it. Now the ac/heater, radio, and the interior lights don't work. What do you think I need to do?
Do you
have the same problem?
Yes
No
Tuesday, February 24th, 2015 AT 10:46 PM

3 Replies

Tiny
CARADIODOC
  • EXPERT
It's doubtful you did anything other than beat yourself up mentally. If the 15 amp fuse was blown, there was already a problem and it blew for a reason. If there was no problem, the fuse would not have been blown, and you wouldn't have stuck the larger fuse in there. If there was no problem, inserting a larger fuse would not cause any damage to anything.

When there is a sudden direct short, a 25 amp fuse is going to blow and protect the wiring. The only time a larger fuse will allow, (not cause), damage to occur is when there is an overload but not a direct short. If, for example, you add a pile of running lights to the tail lamp circuit, there's no short, but each bulb will add to the amount of current flowing in that circuit, and you might end up with 20 amps flowing through wires that are only capable of handling 15 amps. THAT'S where the larger fuse will allow the wires to overheat.

You left out a lot of needed information, like did the 25 amp fuse blow too? What was the symptom that started all this? Did you check for blown fuses inside and under the hood? Where was that 15 amp fuse, inside or under the hood?

The fuses inside protect smaller circuits, and many of them are tapped off larger fuses under the hood that each protect multiple circuits. That means you might have had one dead circuit due to the blown 15 amp fuse, but with the larger one in there, the fuse under the hood blew and took out the other circuits that tap off from it.
Was this
answer
helpful?
Yes
No
Tuesday, February 24th, 2015 AT 11:07 PM
Tiny
REDROCK99
  • MEMBER
Well that makes me feel better. Before all of this happened I would have the radio and the ac/heater on and when I opened the door everything would turn off. So I looked and the fuse for the radio memory and some other stuff in side the car (fuse #8) was blown. That's when I put a 25 amp fuse in and everything worked perfectly. Then I went to push the over head lamp off, and the support broke and the light touched the ceiling of the car, and I think maybe it false grounded or short circuited and probably messed something up. The 25 amp fuse didn't blow, neither did any other fuse inside the car. Thank you so much for helping this is great
Was this
answer
helpful?
Yes
No
Wednesday, February 25th, 2015 AT 7:23 AM
Tiny
CARADIODOC
  • EXPERT
I'm heading out of town shortly but I'll be checking in later tonight to see how you're doing.

If the 25 amp fuse didn't blow fast enough, a larger one under the hood should have blown. If you still don't find that, figure out exactly which circuits and systems are dead and I'll try to find a wiring diagram to see where to go next.
Was this
answer
helpful?
Yes
No
Wednesday, February 25th, 2015 AT 9:24 AM

Please login or register to post a reply.

Recommended Guides