Dave Rethoret

I have a '94 that's taken to blowing the 30 amp fuse that supplies power to the fuel pump, ECM, ign. coil and O2 sensor. It'll suddenly blow the fuse, no symptoms, no warning. It might go for a couple months without problems then toss a couple fuses in fifteen minutes. I've found no bare or broken wires and short of pulling the whole harness out and stripping it down, I'm at a loss. Any ideas?

Pnguyen7

Jmartinez (not exact on name) have a 96 XJ Automatic that are blowing the small 30 amp fuse in our power distribution box. We are not to sure on what it is but I just got the owner's manual shipped to me because the lid doesn't tell you what the fuses run off of. I ran to the corner it blew, I put 10 fuses (not a exageration) to get home 4 blocks away. Sound close to yours?

Dave Rethoret

Yeah, close but not as bad. Did you find the problem with yours?

Pnguyen7

No Still having the problem

ibobm

My son's 1996 XJ is having the same problem. I have to say that I really love driving this car. What a blast! I gets us every where in style. Making the long story sort, the power went out on the freeway in rush hour traffic after going over some uneven pavement (construction) so I had the XJ towed home. The tow truck driver wouldn't tow the XJ unless the rear drive shaft was disconnected and the driveshaft wired out of the way. Of course, the driveshaft broke loose and was ruined by dragging on the ground. Talk about a PITA! I figured I would troubleshoot the blown fuse first...

I am having the exact same problem you guys are. The same fuse continues to blow and I haven't been able to find the direct short yet. I do need to get a proper wiring diagram so that I am not flailing madly and will be on eBay looking for a factory manual after I write this. Have either of you found your problem? Was it a bad component?

I have my fingers crossed. Someone must have come across this before.

captainwoot

Hello, I'll try to help, first get your service info and find out what is connected to that circuit. when the fuse blows that means excessive current flow ie. short to ground(frame chasis etc.) if you take a test light or headlamp bulb and connect it to the terminals of the fuse cavity (while it is shorted) the bulb will light. Then you can start disconnecting components untill the light goes out. when the light goes out you have found your problem, possibly shorted o2 sensor etc. another posibility is the fuel pump is on its way out, causing an excessive amperage draw. Good luck

ibobm

I think that troubleshooting process will work great as a first step. If all the components check out, I am in for a great deal of pain if there is a short in the wiring harness. I didn't see any obvious signs of rubbing or abrasion when looking at the wiring bundles.

I have a gut feeling the three of us are experiencing the same problem. Honestly, I was hoping one of the other folks had already gotten their XJ's running again and I could quickly check their solution.

Your comment on the fuel pump might be right on the mark. My pump has always made a very high pitched noise. None of the other Cherokees I have been in (6) have had this same noise which makes me wonder...

Once I have the proper wiring diagram in my hand, I should be dangerous!

captainwoot

GOOD LUCK! Does this help?

ibobm

CaptainWoot,
YOU ROCK!

My boys and I will get on this tomorrow. By any chance do you have the layout of the fuses in power distribution center? My fuse layout is different than what is shown in the owner's manual. The fuse that is blowing is the only 30 amp mini fuse in the center and I believe it is #11 but best to double check.

Thanks,
Bob

ibobm

okay, I am getting a little more info....

When I pull the relay labeled "ASD" the 30 amp mini fuse does not blow with the key in the run position. With a known good relay in the "ASD" position, the fuse blows.

My next thought:
Is this circuit #12 in the power distribution center? I am some what confused here. I just had shoulder surgery so my thinking is a little muddled. Thank God my son can do the physical work! If I am understanding the schematic correctly, a second relay doesn't exist on the #12 circuit so the ASD relay must control a different circuit.

Any help would be appreciated!

captainwoot

Sorry it took so long to get back to you, still tring to figure the site and stuff out, Hopefully this helps

__________________
Respect is earned, not given
1998 Jeep Cherokee Sport
2005 Jeep Tj

captainwoot

Here is another one, If you don't get a responce from me here drop me an email.

__________________
Respect is earned, not given
1998 Jeep Cherokee Sport
2005 Jeep Tj

captainwoot

Sorry ibobm, I can't find a good complete pic of fuse layout.

__________________
Respect is earned, not given
1998 Jeep Cherokee Sport
2005 Jeep Tj

ibobm

Thank you for all the help. This will give me a little more to chew on. I'll post my results.

ol"blue

Jeep Wiring diagrams

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'97 Grand Cherokee Limited Orvis Up Country 5.2, 4X4
'04 Grand Cherokee SE 4.7, 4X4
'04 Saturn Vue 250 WHP V-6 AWD
'85 Dodge Omni GLHTurbo T-2 282 WHP
'86 Dodge Omni GLHTurbo T-2 397 WHP

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