Trouble shooting a Grand Cherokee

Jeff · July 18, 2012, 12:55:00 AM

Today, my Son's significant other's 2004 jeep would not start. No crank. Battery was good. We pulled the starter off and bench tested it, it was good. Put the starter back on, and we could start it by jumping the solenoid. We shut it off and I started tracing back from the solenoid. No juice to the solenoid wire when trying to crank. So, I went looking in the fuse panel under the hood. There is an ignition switch fuse block (40 amp fuse) I pulled that fuse to test it. Seemed fine. I then checked the block where the fuse came out of. There is power there all the time. I put the fuse back in, and now the jeep starts. Pulled the fuse again and tried to clean up the connection. Put the fuse back in again and it started. Shut the hood, called it good, Jeep won't start. Pull the fuse, put it back in. Jeep starts. Shut it off, wont start. I jumped the fuse with my test light, Jeep starts. So. I switched the fuse out with another 40 amp. Still does it. Pull the fuse, put it back, vehicle starts, shut it off, won't start until you pull the fuse and put it back in.

So, what could I be missing? It's like something gets reset when you pull the fuse. There is a starter relay in that box as well. I switched that out with an identical relay from the fuel pump. No go. Still the same problem.

Any guesses?

sandhills · July 18, 2012, 01:27:16 AM

Are you sure you have a good connection at both ends of the fuse? I'd try to check that with a test light when it doesn't want to crank first (before pulling the fuse).

POSTON WIDEHEAD · July 18, 2012, 04:44:32 AM

say_what This problem is way beyond me. Have you pulled all your hair out yet?

sprucebunny · July 18, 2012, 07:03:37 AM

Check that the grounds are all good.

( The topic title threw me.... like maybe you couldn't bring yourself to put it out of it's misery :D )

Magicman · July 18, 2012, 08:04:34 AM

When it won't start, do you have power to both ends of the fuse/fuseholder?

thecfarm · July 18, 2012, 08:13:51 AM

Could you run another wire,with a fuse,to it? Just for a while to see if that will do it?

Roxie · July 18, 2012, 08:24:58 AM

I'm with Sprucebunny! Aim the gun right between the headlights. :D

Hilltop366 · July 18, 2012, 08:40:26 AM

Sounds like a bad wire or a loose or corroded connection, usually it is the small wire(s) that go to the starter, it would be easier to find if it quit working.

ely · July 18, 2012, 08:43:48 AM

if its got the exposed metal on the back of the fuse it makes it easy to check with a volt meter, it sounds like its one of those enclosed fuse blocks though,so no help there.

does it do this all the time or only when the jeep is up to operating temp.?

Jeff · July 18, 2012, 08:50:07 AM

The jeep had been sitting all weekend here at the house, as the kids were here to visit and swim. Never a prior issue with it. Delana had to leave for work, and that is when we found it would not start, so nope, its a cold jeep although the heat index yesterday was 105° :D

The fuse panel on the jeep is completely enclosed in the back and all the wires run through sealed harnesses. what I found odd, is that the factory connection of the little light green wire going to the starter solenoid is a stake on connection.

Troubleshooting is supposed to be one word I guess. :D

doctorb · July 18, 2012, 09:05:09 AM

I figured that you either had a long-term, sentimental attachment to the Jeep or your gun was having a problem. :D ;D

ely · July 18, 2012, 09:11:43 AM

used jeep? or did they buy it new?

moosehunter · July 18, 2012, 09:16:58 AM

Jeff,
You have a fax #? I can send you diagnoses info.
Have you tried putting the shifter in N? Or move it around in P.
The Ignition switch on that vehicle has a high failure rate. Next time it won't start try turning the key while wiggling it.
mh

Patty · July 18, 2012, 09:20:21 AM

Boy you sure can tell who the mechanics are on the forum. :D

I read the title and thought, hmmmm, Jeff must be a really bad shot not to be able to hit a jeep!

slider · July 18, 2012, 09:37:11 AM

Jeff just ran your problem by the crew at diesel shop.They said when you get it running start pulling relay's until it shuts off had the same problem on a vehicle and it was a relay.Could be in the ecm ,hope not.good luck

Jeff · July 18, 2012, 09:57:28 AM

Quote from: moosehunter on July 18, 2012, 09:16:58 AM
Jeff,
You have a fax #? I can send you diagnoses info.
Have you tried putting the shifter in N? Or move it around in P.
The Ignition switch on that vehicle has a high failure rate. Next time it won't start try turning the key while wiggling it.
mh

Mike, Fax number is the same as the house number. Just let me know the first 3 numbers of the sending number so we don't answer it and hit the fax button. Yes, I've messed with the shifter as that was one of my first thoughts, the park neutral positioning switch. Doesn't seem to have any effect. We have also tried wiggling the key. Everything about the ignition switch seems to be normal. Wiggling the stake on connection does not do anything. wiggling the ignition switch fuse doesn't do anything, but if you remove it, then plug it back in, the vehicle starts. Also, added info, if you shut it off and then try and start immediately, it will start. If you leave it off several seconds, it won't.

whiskers · July 18, 2012, 10:13:59 AM

You could place a starter button on a solenoid bypass for those times it wont crank with the key, or a toggle switch in the relay wire to allow it to reset.

moosehunter · July 18, 2012, 10:42:57 AM

Jeff,
Fax is on the way.
Something to remember with this vehicle (most modern vehicles) is that the ignition switch does not send a signal directly to the starter relay as it used to. The Ign. switch tells the computor that you want to start the engine, the computor tells the relay to start the engine.
Use the wiring diagram and your test light, you should be able to isolate the problem.
Call me @ work if you are still having trouble.
mh

sharp edge · July 18, 2012, 11:34:51 AM

Boss, when it doesn't start it doesn't turnover either?

SE

Jeff · July 18, 2012, 12:25:47 PM

I should have clarified that. The starter will not engage in the problem.

Mike, we got only errors on the fax. It said there was a "power failure" what ever that meant. D may have a warranted on this vehicle yet, so before I dig any deeper, I'm going to wait to hear from her and Jeremy. It's parked behind my truck, but I'm sure my Chevy won't tolerate that if I need to go somewhere. :D

moosehunter · July 18, 2012, 01:11:30 PM

Let me know if you want me to try again.

Jeff · July 18, 2012, 01:37:18 PM

If you would, go ahead and try again.

snowstorm · July 18, 2012, 05:02:37 PM

can you get a scan tool? you can buy them for under a $100. if unplugging the fuse putting it back in works once. sounds like it resets itself. grounds have to be perfect. relays batt cable sometimes it dosent take much. my daughter had a jeep it had its quirks. engine cooling fan would stop working it was the relay. located behind the front bumper. she got rid of it. last time i worked on it was 3 yrs ago. it would start and run few secs then die. i load tested the battery it tested ok but a new battery fixed it. plates must have broke loose in it. batt voltage should be 13.7

Slabs · July 18, 2012, 08:00:18 PM

Start at the excitation termnal on the start solenoid with a test light or voltmeter and work back from there. That is if the relay terminal shows power when the key is turned to start. That will isolate the relay from the rest of the circuit.

Thid is especially important if it's a Delco style starter where the solenoid also engages the bendix.

SamB · July 18, 2012, 08:45:57 PM

Quote from: snowstorm on July 18, 2012, 05:02:37 PM
can you get a scan tool? you can buy them for under a $100. if unplugging the fuse putting it back in works once. sounds like it resets itself. grounds have to be perfect. relays batt cable sometimes it dosent take much. my daughter had a jeep it had its quirks. engine cooling fan would stop working it was the relay. located behind the front bumper. she got rid of it. last time i worked on it was 3 yrs ago. it would start and run few secs then die. i load tested the battery it tested ok but a new battery fixed it. plates must have broke loose in it. batt voltage should be 13.7

Similar experience with my 03 Dakota, don't discount a flakey battery.

shelbycharger400 · July 20, 2012, 10:57:33 PM

scan tool aint goin to help you on this one
If i remember right. power goes from battery to fuse, to ignition switch, low voltage side of relay control , then ground. fused battery through relay to starter via the one wire terminal. What motor is in this jeep? the 5.2 L? im guessing.
If I was you, I would have pulled the tin cap off the back of the starter on the starter, it has 3, 8 mm nuts on it. The contacts in their get dirty and arc corroded somewhere around 140k mi on the speedo (althou my stepdads diesel was 190k) , first mark all parts with a marker or scribe, pull the 2 screws off the back of the starter body, carefully pop the back cover off and take a look at the brushes. these starters are so easy to rebuild its silly.
Pop the starter out and look at those first. Still actin up, unfasten the pdc (power distribution center, carefully turn it on its side and pop the back cover off and look at the buss bars for water and corrosion, and carefully look at the wires next to the terminals. If you see one that is bulged or puffed up, it is corroded inside. I dont have a picture of what it looks like, but u will see it if it is. Remember you can have voltage and NO flow .

Jeff · July 20, 2012, 11:01:22 PM

Nothing wrong with the starter, had it off and bench tested it.

shelbycharger400 · July 20, 2012, 11:23:57 PM

o, hey, how is the supply wire from the bat to the starter? i know they are molded in.
is it swelled by the battery terminals?

just because it bench tests dosnt rule it is "good" ive been down that road, take it out..bench test good.. put it back in.. NOthin .
where you cycle the key back and forth several times quickly and i mean fast. then all of sudden it pops off ... solenoid. the occasional hit and miss.. ect. its all variable baised upon the contacts and the disc inside. slow crank time... battery or the brushes. I will pop one apart tomorrow and give you a picture of inside of one.

trust me here boss.. its way easy to check this first before chasin the electrical ghost.

Jeff · July 20, 2012, 11:27:26 PM

Trust me, there is nothing wrong with the starter.

I ran a jumper to the solenoid and it will start every time.

shelbycharger400 · July 21, 2012, 10:35:12 AM

ok then.. pull the pdc apart and look for corrosion

Warbird · July 21, 2012, 12:08:32 PM

How long have you left the battery disconnected at one time? My hunch is it's the computer messing up.

Jeff · July 21, 2012, 09:00:51 PM

The battery was unhooked for a couple hours at one point when we had the starter out of it. I'm sure its a weak connection somewhere or a sticky relay. It may be temperature related as well. We needed to move it today to get my truck out, and it started right up. Several times. Its in the 70's today, and was in the 90's when we were having issues.

Jeff · October 18, 2012, 11:00:21 PM

I wanted to update this topic, because the answer to the problem was found today. It is not what I would have ever thought.

The vehicle started doing the same thing today. Dee called to find out what we had done to get it to start last time. I could not remember exactly what fuse it was I was pulling, so she called the lot where she bought the Jeep. As it turns out, the vehicle was bought at a buy here pay here lot. If your monthly payment does not clear within 3 days after the due date, they have some sort of device installed where they can disable the ignition remotely by sending out a signal. Dee had made her payments both times right on the due dates but somehow the payments did not get registered before they activated the vehicle's start disabling. So, it turns out, I was able to over-ride their system without knowing there was a system. I guess it is a bit embarrassing, but at least now we know. :D

WDH · October 18, 2012, 11:04:18 PM

No Payee, No Drivee.

isawlogs · October 18, 2012, 11:26:49 PM

Legaly speaking... can they do that Jeff ??? Just curious... and did they tell Dee of this great system of theres? :-\

Jeff · October 18, 2012, 11:39:22 PM

I gotta think they have to tell you, but as far as I know, if they did, she forgot or paid no attention, but they did tell her today. Now she knows and I bet the payment is in early next month. :D

thecfarm · October 19, 2012, 07:41:33 AM

I guess we are better at trouble shooting sawmills than Jeeps. :D

SPIKER · October 19, 2012, 08:11:36 PM

boy I would guess that would be one thing I would be getting rid of, no big brother stuff for me!!!

shelbycharger400 · October 19, 2012, 08:24:50 PM

probably just under the pannel below the steering wheel. Most likely it will look like a remote start box. Only other places I have seen stuff like that is a 2x2x4 box under the dash pad, REAL easy to spot as their will be wires all taped up, a bundle the size of a baseball, then feed into the magic box. the splices will be into the red and yellow wires comming from the ignition switch

I too would be removing this device!
They are a Safety hazzard!
they can give you a song and a dance all they want (the seller) then you can tell them they are in violation of a federal law, cant remember how it goes but its an unautherized alteration of a motor vehicle. Basically if the vehicle burns up or crashes the installers and the company that made the device are in hot water. Who goes to say they turn the vehicle off while your going 70 down the freeway? NO power brakes or power steering for the 100lb 5ft 4 behind the wheel? ugh what is wrong with people that dont think.

Jeff · October 19, 2012, 08:36:47 PM

The device doesn't have the ability to shut the vehicle off. Only to keep it from restarting once it has been activated and the car shut off. There is no big ball of tape or any such thing, as I was all over under the dash around the steering column. I don't know exactly how it works, but I know what it does. It is an interrupter in the starter solenoid circuit.

I just found this with the first search.

http://www.paytimeonline.com/

Jeff · October 19, 2012, 08:43:50 PM

I just did a little research and there are several companies offering the device and the service and from what I can see it is perfectly legal.

Mooseherder · October 19, 2012, 08:48:05 PM

Why the dirtyrottenturdmobilejerksterswithnothinbettertodo! :D

Holmes · October 19, 2012, 08:57:27 PM

I did not know they made things like that. Hmmm I wonder if they make one for toilets? ;D ;D

shelbycharger400 · October 19, 2012, 09:01:36 PM

Thanks Jeff!

I have never had to deal with one of these, maybe I did and eliminated it.
I will remember this one!

I was under the asumption they could shut it off at will , that would be illegal.

This dose bring up a good memory from back in the day. One of the techs was taking all the gravy tickets, even took a few of my jobs I upsold. The russian next to me was up to something when I was busy doin something. He was my mentor and recieved 20 percent of what I did as credits, I got 80 percent Journeyman. he fixed him ;D, told me bout it after he left for a test drive. IT was a long time before he got back. My mentor stuck a white ISO relay in the asd relay place in the pdc. The white ones in chrysler are time delay relays and B vans used them. After 15 minutes they time out. The asd or Auto Shutdown Relay controls everything. He came back and groaned bout it for a while. He was stuck on the side of hwy 7 til he figured it out. it never did fix his grabbin greed, but the layoffs and closing of the shop kinda pinched him a bit. Heard rumors out HE was the only one that wasnt union member and was payed WAYY over scale.

SPIKER · October 19, 2012, 09:36:23 PM

Jeff I would imagine that it is setup as a FLIP FLOP type relay in-line with the start circuit. that is why it resets when you kill the power and re-attempt the start.

Look for something like a small black relay box it probably has a factory looking plug with 3 or 4 wires on it. if you have a "haynns Book" you should be able to trace the wiring back pretty quick as you already stated only a couple items in that circuit...

Mark