Major Electrical Issue? 60A Fuse Blowing ...
#17
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
But that 60 Amp fuse blowing, bothers me for some unknown reason.
I mean when you put the switch in START, it looks to only be feeding the Starter Relay.
It has to be doing more than just the relay ..... am I right?
#18
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From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
Look at the wiring diagrams in your factory service manual.
#19
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From: Lost in the wilds of Virginia
Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
Ah, well, maybe not then....
Oh. Dat 'splains it!
Again, I have not messed with this circuit and don't have a diagram, but if there is a starter relay, it's typically going to energize the solenoid directly on the starter.
But it shouldn't need anything like 60 amps, so....
Maybe that 60 amp circuit feeds the solenoid itself??
#20
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
#21
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
According to the Starting System Schematic that I have ... same as posted by CCKen in Post #10 a 40 Amp Fuse ( F7) feeds the solenoid.
I am gonna try to find time tomorrow to look a little deeper in the circuits.
It/s been a few years since I have had to dig into a wiring circuit like this ..... but troubleshooting comes easy to me.
Divide And Conquer < ---- the method I like to use.
I am gonna try to find time tomorrow to look a little deeper in the circuits.
It/s been a few years since I have had to dig into a wiring circuit like this ..... but troubleshooting comes easy to me.
Divide And Conquer < ---- the method I like to use.
#22
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
The plot is thickening ......
A little research shows that Fuse 6 feeds the following ......
Ignition Switch - Engine Controller, Fuel Pump Relay,
Automatic Shutdown Relay Coil.
So those things should be disconnected to troubleshoot ????
Pull the ....
ASD Relay
Fuel Pump Relay
Engine Controller ????? PCM I assume? There are TWO fuses for this one!
A little research shows that Fuse 6 feeds the following ......
Ignition Switch - Engine Controller, Fuel Pump Relay,
Automatic Shutdown Relay Coil.
So those things should be disconnected to troubleshoot ????
Pull the ....
ASD Relay
Fuel Pump Relay
Engine Controller ????? PCM I assume? There are TWO fuses for this one!
#23
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
If one of those were shorted, the fuse would blow BEFORE I turned it to START ....
UNLESS .......
Something is NOT shorted, yet pulling enough current to put it on the hairy edge and going to START is the straw that breaks the camels back ?????
UNLESS .......
Something is NOT shorted, yet pulling enough current to put it on the hairy edge and going to START is the straw that breaks the camels back ?????
#24
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Joined: Apr 2010
Posts: 127
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From: Puerto Rico
Year: 1995
Model: Cherokee (XJ)
Engine: 4.0L I6 242Ci
I also have a 95 XJ and it blows the same Maxi 60 amp fuse when i hit a big pothole or something. In my case i mess around with the buzzer thing (Annoying sound) in the fuse box inside cabin when fuse blows i wiggle the cable and put another fuse and it starts. A couple of days ago i disconnect the fuse assembly and reattach the buzzer thing and at the moment no more blown fuse. I dont know if that shorted something. Hope it helps ya
Buzzer thing next to green connector
Buzzer thing next to green connector
#25
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From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
#26
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
However I only have one here .... and if that goes, I got nothing.
Trying to get a new switched today to replace the one I pull out ..... if I can.
I was lucky enough to score the switch/lock/3 keys in one unit so I won't have to mess with mating the lock mechanism to the switch itself.
Tried that once before and could not get a proper fitting switch assembly for some reason ...... even sent it to a shop to have them try. We think someone may have changed something along the way.
#27
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
Jeep puts in a 30 Amp when a 20 Amp will suffice!
On the other hand, nothing wrong with installing an under rated fuse if it works.
What's insane is putting in a 40 Amp because the 30 Amp blows out!
#28
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From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
I'm tempted to throw in another switch assembly just to see what happens.
However I only have one here .... and if that goes, I got nothing.
Trying to get a new switched today to replace the one I pull out ..... if I can.
I was lucky enough to score the switch/lock/3 keys in one unit so I won't have to mess with mating the lock mechanism to the switch itself.
Tried that once before and could not get a proper fitting switch assembly for some reason ...... even sent it to a shop to have them try. We think someone may have changed something along the way.
However I only have one here .... and if that goes, I got nothing.
Trying to get a new switched today to replace the one I pull out ..... if I can.
I was lucky enough to score the switch/lock/3 keys in one unit so I won't have to mess with mating the lock mechanism to the switch itself.
Tried that once before and could not get a proper fitting switch assembly for some reason ...... even sent it to a shop to have them try. We think someone may have changed something along the way.
Take a look at that starter wiring diagram. See that connector C224. That's connected to the ignition switch. Many functions go through that connector. This connector has been known to melt. Check it out.
#29
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From: Bel Air, Maryland 21015
Year: 1995
Model: Cherokee
Engine: 4.0
I am aware of the issues there, and almost EVERY Cherokee I have been in ( XJ 7 Grand ) have burn indication on one or more of the wires.
I have not seen one actually melted yet, but I have found quite a few with burned insulation on wires from excessive current.
In fact I have two of them in front of me right now and on one overheating is indicated on two wires, and on the other overheating is indicated on only one.
That connector is actually rebuildable more easily than most. Pop out the red retainer and use a tiny flat blade to release each conductor.
Whenever I go to the scrap yard, I harvest that connector along with 8 inches of wiring behind it for use in future repairs.
I also look for other connectors that are typically burned/melted and if good pull them. Another popular melting connector is the one for the HVAC fan control.
#30
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From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
Up to 1994 there is a 25 Amp fuse in #5 slot, 95 & 96 it was upped to a 30 Amp fuse in #5 slot (HVAC). Don't know why they would up it to 30 Amps, unless it was to compensate for deteriorating blower motors (which are junk to begin with and draw more Amps as they age). I think the higher Amp fuses are to absorb any surges when initially turning the fan to high so I see no need to lower the fuse Amp rating from book value.