Intermittent starting issue

2000 Jeep Cherokee Sport 4.0

Intermittent starting issue where I turn the key( feels normal ), hear the starter relay click, all dash lights on as normal. Starter does not turn over or make a sound. Using multi meter reading 12.6 v at the battery post, found ground was good at the starter. Used a test light to see that there was NO 12v signal at the ignition trigger wire at the starter while turning key to the run position. I jumper the start to confirm the working starter, started right up, so good starter. Ran it for a bit thinking thinking issue is at the ignition switch or NSS. Turned the engine off thinking it wouldn't fire up but sure enough it did start no problem. A few more stop and go errands to run and the Jeep shows no problem starting normally.

My next step is to clean all connection from the battery to the starter, they're nt the cleanest I'd admit. How do I test a faulty ignition switch?. I've seen how to bypass the NSS for testing.

Thanks in advance

if you hear the relay click, then and the lights in the dash turns on, then the switch is probably working? your problem sounds like a solenoid.. of course start by cleaning connections, next time the problem occurs, check the small wire on the starter for +12v with a test light, WHILE holding the key to start position. If you have juice there then it's in the solenoid, if you don't well you need to go back that wire find out if there is another solenoid(relay) before that.

When the brushes get short from fair wear and tear, the solenoid can try to work but without the motor spinning up, it won't really engage the bendix and drive gear. How to say this and be understood? The contacts in the solenoid engage before the fork pushes the drive gear all the way forward, the spin of the motor finishes the process. If the motor doesn't spin up it is usually because of worn brushes.

When the brushes get worn down, contact can be iffy, sometimes a little more current will do it, sometimes it can just be sporadic.

I'll tell you what I do in that situation: I slap the shifter forward in park and try again, then shift to neutral and try again. I try to engage the starter with the headlights on and see if the headlights dim. I whack on the side of the starter with with a hammer (or whatever is handy) and try again. Don't hit it so hard it breaks something, but hard enough to jar the brushes a little and maybe seat them a little tighter so they make better contact, this does work.

If your oil filter adaptor is leaking onto the starter, the brushes can get oil soaked and cause the same issues. Muddy water can get into the brushes and when it dries, it leaves a non conductive coating of mud on the brushes. Sometimes just cleaning the starter out helps. GoJeep had a good writeup on this http://www.go.jeep-xj.info/HowtoStarterClean.htm

Hitting the starter with a hammer should be last resort.. after checking for proper voltage. And if you DO hit it and it DOES turn, don't ever rely on that starter again, unless you at least take it apart to inspect it. And I do NOT mean taking it off the engine and looking at it...

Just recently had this same issue with this on my buddy's 2000 XJ. All the lights worked, radio, ect.. so we didn't suspect the battery... took the starter out and had it tested and it was fine. Ended up being the battery. He did some searching around on the internet and found some info about how on the newer model XJ's if the battery isn't holding a certain % of a charge that it does something with the computer and doesn't allow it to start. After popping in a spare battery I had it fired right up and has been fine ever since.

peelman said:

My next step is to clean all connection from the battery to the starter, they're nt the cleanest I'd admit. How do I test a faulty ignition switch?. I've seen how to bypass the NSS for testing. Thanks in advance

Click to expand...

Cleaning all the connections and grounds and making all the connections tight & shiny should be # 1 on your list.

If the starter relay or ANYTHING clicks...it's not the NSS.

Starter relay clicks. So your saying the starter relay is the last signal to engage the starter?.

peelman said:

Starter relay clicks. So your saying the starter relay is the last signal to engage the starter?.

Click to expand...

Did you have your battery tested. I would strongly suspect the battery since I have seen the issue you describe on two separate jeeps (2000 xj and 2009 liberty) be caused by a battery that wasn't holding enough of a charge.

12.5 with my multimeter

peelman said:

12.5 with my multimeter

Click to expand...

I would take it in to a parts store and get a load test done on the battery

10.4ish on my load tester. That's still ok. Can't find a date in the battery. Interstate battery

foress_89 said:

Hitting the starter with a hammer should be last resort.. after checking for proper voltage. And if you DO hit it and it DOES turn, don't ever rely on that starter again, unless you at least take it apart to inspect it. And I do NOT mean taking it off the engine and looking at it...

Click to expand...

Like most things you have to do it with feeling, hard enough to jar the brushes, but not so hard the internals destruct. This can tip you off, that it is in fact the brushes causing the issues. Weather, stuck someplace without tools or the proper test equipment, you do what you have to.

I still have my original 87 starter, it's in my 96 and has been for the last couple of years. Other than a couple of new brush sets, some cleaning, some grease in the reduction bears and bearings, it work just fine. It has absorbed numerous whacks with a hammer and it hasn't caused any issues for the last 26-27 years.

Voltage doesn't mean much, you can get good voltage through a single strand of wire the size of a human hair, amperage is what turns the starter over. Or maybe better said, Watts (Volts X Amperage = Watts). Low voltage is an indicator, no voltage a troubleshooting tool, good voltage doesn't mean you have enough Amperage flowing through the wire, connections, ground or cables.

I had to replace the starter relay to starter solenoid wire on my 96. Not sure if the 2000 is the same or not, but I followed the starter solenoid wire back to my PDC and found a handy single wire connector on that solenoid wire just before it ran into the PDC, to the starter relay.

Sorry please clarify from the starter solenoid wire traced back to the PDC, you found a "handy" single wire... What did you do?.

peelman said:

Sorry please clarify from the starter solenoid wire traced back to the PDC, you found a "handy" single wire... What did you do?.

Click to expand...

I tested for voltage at that connector and it was there, then I tested for voltage at the solenoid trigger wire connector and had no voltage, this told me the problem was between the two points.

If you test no voltage, test again with a different ground. It is easy to get it wrong, not have a good ground or maybe where you are testing is oil covered.

The 2000 may have the same single wire connector starter relay out wire, outside the PDC, it may not. If it is there on yours, it is a good test point.

Question?` Is the outside of your starter oil covered?

Interesting. I used battery ground. Possible oil at the starter solenoid I did scrape away some. Going to take that solenoid trigger wire off and test while off the starter. My 2000 has the single wire off the starter solenoid into the loom to PDC, bit sure what happens there.
Lol, is there a Cherokee without some oil on their starter?. I was thinking the same thing, but I'd hate to drop cash on something that's not definite, know what I mean?. Thanks

peelman said:

Interesting. I used battery ground. Possible oil at the starter solenoid I did scrape away some. Going to take that solenoid trigger wire off and test while off the starter. My 2000 has the single wire off the starter solenoid into the loom to PDC, bit sure what happens there.
Lol, is there a Cherokee without some oil on their starter?. I was thinking the same thing, but I'd hate to drop cash on something that's not definite, know what I mean?. Thanks

Click to expand...

That oil covered starer can cause issues, I sure don't know how, but oil does get inside and can coat the brushes, which causes iffy starts.

I plug up the leaks as I find them, but my starters are usually oil covered more than clean. Just something to check out. I've spray cleaned (brake cleaner works fine) the oil off of the brushes and armature before and had the starter work just fine. And at the same time I check out the brushes to see if the brush wire is hitting the brush holder and/or the brushes look way short.

Taking the back off the starter is no big deal, I mark the pieces (three sections) just in case they shift (rotate) while you are trying to get the end cover off. It usually takes two people and a little cussing to get the end cover and the brushes back on. You have to figure out some way to compress the four brushes to get them over the armature. Like most things the first few times it is a pain, then you get better at it.

watch out for springs, and put them back where they belong. If it goes in the first try without pain, take it apart to check lol.

FYI, you can use any year XJ starter, IF you get an older one, you will have to modify the stock connector . But early model is way cheaper than later model starter.

Good tip thanks. Other than the connector, the rest compatible?. There like a $50-70 difference.