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Topic Review (Newest First)
07-13-2013 10:06 AM
shittybilt thanks for the wiring diagram

anyways I know that its the light green wire that runs to the coil is not getting the proper voltage.. the diagram I beleive showed that it runs back to the ecu? Im not the best at reading them and the diagram was tiny and blurred on my computer... I replaced the computer and the line from the coil to the computer seems to be good.. any other ideas ?
07-11-2013 11:16 PM
91yjTurtle shittybuilt i just had a problem just like you are having
read here
coil wire diagram also
07-11-2013 08:03 AM
western196611 The box that you are referring to is the main computer. I believe that the ignition module is close to the fire wall in the center. My yJ doesn't have an ignition module,
07-11-2013 07:25 AM
shittybilt Still no results. Did find that the light green wire from coil isn't showing proper voltage. I need to trace the wire but surprisingly no diagram in manual. Anyone know the wiring on the coil ? Where does the light green wire run? To ignition module ? Is that under the coolant reservoir on a yj ?
07-02-2013 05:39 PM
shittybilt Is there a way to check the ignition switch itself ? Aside from that I feel like I checked everything. This sucks
07-02-2013 05:26 PM
Pittsburghwrangler If that doesn't work all I can tell you is to start at the battery and work your way through the ignition system piece by piece, just check everything
07-02-2013 05:22 PM
shittybilt The right side wire (red ) comes up with -9.40 middle (black prolly ground). 0v and the left side comes up with -4.9

Should these numbers be negative ?

Edit. :: actually my tester must e off. My battery even reads negative. So with that said then I'm
Getting the proper direct voltage to the crank sensor
07-02-2013 05:16 PM
shittybilt Still no luck after all that. Tried a new ecu and replaced coil plug off the harness. Checking for 5v at crank sensor now.
07-02-2013 08:17 AM
Jdrice82 Unplug your CPS, turn the switch on and check the wires coming from the ECM. It should show 5 volts. Their is also a process to check the grounds. Google it. Crank it over with the CPS unplugged, leave the switch on and plug the CPS back in then try to crank it. It worked on mine.
07-02-2013 02:25 AM
c5wagner Ignition control module? I don't know if your car has one like my 4.2l
07-01-2013 09:05 PM
shittybilt Checked fuses. Still no luck. Any other ideas? !
06-27-2013 09:14 PM
AllMudd It is right above your left foot as you sit in the drivers seat. As you look at the box it's labeled ign/(something else I'm not around the Jeel right now) its the lower right fuse.
06-27-2013 08:59 PM
shittybilt Yes I am getting fuel.but no spark from coil. Where would the ignition fuse under dash be at? Ill check that. Didntnget a chance to check tonight since it rained heavy.
06-26-2013 11:13 PM
Originally Posted by The Silver Gorilla View Post
Are you getting fuel at the rail?
He said he's getting no spark.......confused on this question?

There is a Ignition fuse under the hood 40 amp by the battery in the power distribution panel (PDP). Also there is a Ignition fuse under the dash 15 amps. Also just saw an Auto Shutdown relay in the PDP not sure what it does but try swapping it out for your horn relay and see if it helps.
06-26-2013 10:50 PM
jk'n You are certain it is spark? I don't know if the terminals are accessible across the primary of the coil but you could try measuring DC voltage there. It won't be battery voltage but it won't be zero either. Depending on duty cycle of the circuit it would be lower than battery voltage.
06-26-2013 10:43 PM
The Silver Gorilla Are you getting fuel at the rail?
06-26-2013 09:46 PM
please help ! ignition problems

Newbie here to this forum . Been pulling out my hair tryig to figure out the problem. Hopefully someone can help. 94 2.5 yj. 100k miles. Ran good till one day it died. Towed it home now it does not start

I found no spark so I replaced the whole distributor. Then found that I never had spark to the distributor so I replaced the coil. Still no spark coming from the coil. Read online about a crank sensor so I replaced that as well. Checked all wires grounds and fuses and still no spark from coil. It does throw trouble code 54 which seems to be distributor related but Im not getting spark to the dist..

It cranks and other accessories seem ok so I doubt its the ecu.
Could it be the ignition switch? (How can that be checked)
Are there any under dash fuses connected to ignition?

Any help at all will be great because at this point aside from using a voltmeter on all wires-i have nothunh else to go by.

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