Shorted ECU?
04-06-2012, 10:39 PM
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Year: 94
Model: Cherokee
Engine: 4.0 Stroked - 4.7
Shorted ECU?
Well I took the fam out last weekend to do some trail riding and during the ride the O2 wire somehow fell into the tri-pipe of my header. Didn't notice it til I was driving back and the CEL light came on and engine died. When I discovered the problem, the wires completely melted and looks as though grounded itself to the headers. I've since replaced the wires but no-joy on getting the motor cranked. Checked all fuses, good.
I tried to do the manual CEL blink test but all I get is a solid light. I dont have a code reader either. But from what it seems like is that I may have shorted the ecu... any suggestions other than going out and buying a reader at this point? Its a 94 XJ.
I tried to do the manual CEL blink test but all I get is a solid light. I dont have a code reader either. But from what it seems like is that I may have shorted the ecu... any suggestions other than going out and buying a reader at this point? Its a 94 XJ.
04-10-2012, 08:54 PM
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Year: 1995
Model: Cherokee
Engine: 4.0 HO
Something similar happened to my friends 93 or 94 YJ, Same computer and everything. He had to trace thru the schematics to find that a fuse was mis-labeled fuse. But you checked the all the fuses so the ECU could of fried. Try to find a friend with a similar jeep and swap ECU to see if yours is toast
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04-13-2012, 06:39 PM
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
oh well read this yet.....https://www.cherokeeforum.com/f2/96-...er-hood-19793/
Last edited by freegdr; 04-13-2012 at 06:51 PM.
04-13-2012, 08:51 PM
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Year: 94
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Engine: 4.0 Stroked - 4.7
Well I did spot the issue - it was that retchid 30A fuse... apparently with the ignition off it will still read 12V on both sides of the poles (not uncommon). Its always good to check with the meter but nothing beats a good pair of needle nose and your own eyes. Thanks for the info though. I will save the wiring link in my favs.
From reading the post you linked, helped me understand the O2 sensor and the fuse. I grounded out the wires on my O2 sensor to the exhaust which caused the 30A fuse to blow. Bought a new ecu for nothin.
From reading the post you linked, helped me understand the O2 sensor and the fuse. I grounded out the wires on my O2 sensor to the exhaust which caused the 30A fuse to blow. Bought a new ecu for nothin.
04-13-2012, 08:52 PM
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Well I did spot the issue - it was that retchid 30A fuse... apparently with the ignition off it will still read 12V on both sides of the poles (not uncommon). Its always good to check with the meter but nothing beats a good pair of needle nose and your own eyes. Thanks for the info though. I will save the wiring link in my favs.
From reading the post you linked, helped me understand the O2 sensor and the fuse. I grounded out the wires on my O2 sensor to the exhaust which caused the 30A fuse to blow. Bought a new ecu for nothin.
From reading the post you linked, helped me understand the O2 sensor and the fuse. I grounded out the wires on my O2 sensor to the exhaust which caused the 30A fuse to blow. Bought a new ecu for nothin.
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