No power to coil?
08-08-2009, 09:06 PM
#16
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Year: 1991
Model: Cherokee
Engine: 4.0
Oh...one other thing, did you check or do you know how to check for any DTCs (diagnostic trouble codes) by counting the "check engine" light flashes? If so, what codes, if any, were displayed?
08-08-2009, 09:22 PM
#17
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Year: 1995
Model: Cherokee
The light is not on but I will run out real quick and check it. I haven't done this in a while so refresh my memory. Turn the ignition on and off 3 times? correct?
08-08-2009, 09:32 PM
#18
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Year: 1991
Model: Cherokee
Engine: 4.0
Cycle the switch on-off-on-off-on within 5 seconds and count the flashes. The last code will be 55, 5 flashes, pause, 5 flashes. (Just turn the switch on, do not crank the engine).
08-08-2009, 09:35 PM
#19
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Year: 1995
Model: Cherokee
Tell me if this sounds right...
1 pause 2 pause 3 pause 5 pause 5
that would be one flash, pause, two flashes, pause etc.
08-08-2009, 10:09 PM
#20
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Year: 1991
Model: Cherokee
Engine: 4.0
The first code looks like 12 and the last looks like 55, don't know about the 3...all codes are 2 digits. Maybe you missed a digit...try it again when you get a chance.
08-08-2009, 10:18 PM
#21
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08-08-2009, 10:31 PM
#22
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Year: 1991
Model: Cherokee
Engine: 4.0
12 is battery disconnected within last 50 key on cycles, 35 is cooling fan relay (maybe your electric fan has or had a problem), 55 is end of code sequence. None of these should be causing your no spark problem. Try the test light tomorrow...good night.
08-08-2009, 10:42 PM
#23
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Year: 1991
Model: Cherokee
Engine: 4.0
35 was probably set when you swapped the fan relay with the ASD.
08-09-2009, 10:21 AM
#24
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08-09-2009, 10:58 AM
#25
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Year: 1991
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OK, sounds like you never saw any voltage at the dark green/orange wire during cranking. If that is the case, next step is to examine the 60 pin connector on the PCM. Remove the connector and check for any corrosion, bent, spread, or pushed-in pins on both the PCM and the connector...do a careful examination. Make sure there is no corrosion (usually green) where the wires enter the connector pins.
08-09-2009, 11:16 AM
#26
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Year: 1995
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OK, sounds like you never saw any voltage at the dark green/orange wire during cranking. If that is the case, next step is to examine the 60 pin connector on the PCM. Remove the connector and check for any corrosion, bent, spread, or pushed-in pins on both the PCM and the connector...do a careful examination. Make sure there is no corrosion (usually green) where the wires enter the connector pins.
To me all of the pins looked very clean. I took some pictures and you can tell me what you think.
08-09-2009, 11:20 AM
#27
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Year: 1993
Model: Cherokee
Did you even try a new coil. You can always return it if it doesn't work. I had the same problem and I couldn't tell anything with the multi-meter. So I just replaced it and it works fine.
08-09-2009, 11:25 AM
#28
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No, I have not tried a new coil. I dont want to sound ungrateful for the advice but if there is no power coming to the coil do you think that a new one would fix it?
08-09-2009, 11:29 AM
#29
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Year: 1993
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I went through a similar situation and could not get a reading. So I took a chance and just bought one and made sure I could return it. Before I unbolted the old one I plugged the new one in just to try and it worked. The only reason I suggested that is because I went through the same thing. I drove to a friends house and couldn't drive home, it just quit on me. It is a quick check before going through everything else. Just trying to help. Is the ground to your motor clean and making good contact?
08-09-2009, 11:46 AM
#30
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Year: 1991
Model: Cherokee
Engine: 4.0
Judging from the pics, things look pretty clean.
See if you have continuity (use your ohmmeter) from pin 57 on the 60 pin connector to the coil connector...this is the dark green/orange wire.
See if you have continuity (use your ohmmeter) from pin 57 on the 60 pin connector to the coil connector...this is the dark green/orange wire.