Manual transmission 98 XJ no start

I have a 4.0L 98 XJ that won't start, and it's either the sensor that tells the computer when the clutch is engaged/disengaged, or the ignition switch. When i turn the key to start (regardless of clutch engagement) nothing happens. All the electronics work fine, battery isn't dead, nothing. So what wires should I jump in the ignition switch to test if it's the ignition switch or the clutch sensor?


I've already tried jumping the terminals at the plug for the clutch sensor and nothing changed. Also the "feel" of turning the key hasn't changed at all, my guess would be if the ignition cylinder had become misaligned enough to where I just couldn't turn the key far enough to start it, it would feel different, correct?

First, put it in neutral parking brake set, then jump the starter solenioid main B+ to the small lead. It should crank if the battery, cables, starter and solenoid are good.

If it cranks, then check the starter relay--can't tell you which one on the late models.

If you haven't had the starter checked out yet, I would do that first. You can either set a VOM at the starter to see if you get power when the switch is turned, or just remove it all together and have it bench tested. My '98 has similiar symptoms to yours, and it was the starter that was giving me grief.

Also, check the starter relay in the PCM under the hood as another possibility.

You can also by pass the clutch interlock just to make absolutely sure that is not the problem. I found a green connector with yellow wire just looped back to the same green connector. It was taped under the dash right next to the clutch interlock connector. To my surprise the factory included this bypass under the dash for you. You just unplug the green connector with the yellow wires and plug it into the other green connector, with the yellow wire looped back to itself.

Ivan said:

If you haven't had the starter checked out yet, I would do that first. You can either set a VOM at the starter to see if you get power when the switch is turned, or just remove it all together and have it bench tested. My '98 has similiar symptoms to yours, and it was the starter that was giving me grief.

Also, check the starter relay in the PCM under the hood as another possibility.

You can also by pass the clutch interlock just to make absolutely sure that is not the problem. I found a green connector with yellow wire just looped back to the same green connector. It was taped under the dash right next to the clutch interlock connector. To my surprise the factory included this bypass under the dash for you. You just unplug the green connector with the yellow wires and plug it into the other green connector, with the yellow wire looped back to itself.

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I was actually hoping to do that regardless, thanks for the info. The only reason I'm leaning more towards that sensor is that a week ago it let me start it without touching the clutch (which it usually doesn't do) so I would assume that it's malfunctioning again, just not to my benefit.

Is there more info on jumping the starter? I'm sure I could figure it out but it would make my life easier if there's something I can just follow. The lights don't dim or anything when i try to start it so I'm assuming the starter isn't jammed, because I have a shitty battery so I would definitely notice that much of a strain.

Sparknotes: Best guesses for problem is either clutch interlock circuit not closing, or bad starter.

Edit: I would also like some info on replacing my ignition switch with toggle switches. Is there a good source of info on that? I'm more mechanically inclined than most but I'm also lazier than most...

I had a CPS failure that had the same symptoms....

just to clearlify, does the engine turn over(starter engages) but the engine doesnt start?

or, does the engine not turn over at all?

The engine doesn't turn over at all.
A bad CPS doesn't prevent the engine from turning over, does it? I don't think it does but I'm not confident enough to say.

XJ98Jeep said:

The engine doesn't turn over at all.
A bad CPS doesn't prevent the engine from turning over, does it? I don't think it does but I'm not confident enough to say.

Click to expand...

It's not supposed to.... that's why I was battling that issue for a long time couple years ago then someone suggested for me to swap out the CPS and to my surprise it worked. The odd thing was that I was not getting ANY failure codes or any indication of an error. Only symptom I had was that when I rotated the key to start position nothing happened: no noise, no click, no start... nothing.

Have you tried the rolling/pop the clutch method? If so, does it run then?