No start... or crank for that matter

[XJeepin06]

So my wife has a 04 kj 3.7 auto 2wd. I replaced the aftermarket radio with another, I have replaced many radios, but I blew the fuse for the radio, map lights...etc. I replaced the fuse, now everything inside works, so does the wipers, headlights. but when you turn the key to on the fuel pump does not prime, starter does not do anything not even click. So I thought it was the ignition switch, bought a new one, no worky. I have power from the wires on the ignition switch. I have power to the starting relay at the right time/pins. Check all fuses. I have continuation from the fuse block to the starting solenoid but no power being transfered. I made a shorting wire and held the key at start while turn the starter, nothing. Tryed the old XJ trick of neutral rocking the vechicle back and forth that didnt help. the reverse lights work as normal.

Anyways thanks for the help in advance,
Kevin

 

[Bikeflyer]

So you did try to hot-jump the solenoid? Remove the starter and bench test it. That said, I don't know how hard that is, but it sounds like you can handle it. If the starter passes the test on the bench, then it is something else. If not, have it rebuilt.
The other items have apparently been dealt with other than of course the solenoid. If you have power and get no click at all, the solenoid could be jammed.

 

[liberty84]

Just a thought.......what about the relay for the starter on the relay box under the hood, any chance is got blown too?

 

[XJeepin06]

I went and had the starter benched, it passed. I switched the starter relay with the blower motor relay, still nothing, I also did some resistence checks on the starter relay, and its good. I went and talked the my jeep dealership, he said this does not sound good. He walked me through every test I can do, I have done them all. He is thinking the PCM might have lost ground and fried itself. $900. YAY not. So I guess monday I will have it towed down there. Maybe its time to trade it in. 140k mileage.

Thanks for the replys, any other ideas?

 

[kb0nly]

I went and had the starter benched, it passed. I switched the starter relay with the blower motor relay, still nothing, I also did some resistence checks on the starter relay, and its good. I went and talked the my jeep dealership, he said this does not sound good. He walked me through every test I can do, I have done them all. He is thinking the PCM might have lost ground and fried itself. $900. YAY not. So I guess monday I will have it towed down there. Maybe its time to trade it in. 140k mileage.

Thanks for the replys, any other ideas?

If you can fix it for a grand or less i would. But then i'm really attached to my KJ now and i would.

One question, is it bought and paid for??

If it is save some money overall and just fix it.

 

[tjkj2002]

Have you checked the ASD relay? It's the primary grounding relay for pretty much everything to do with fuel and spark on the KJ.

 

[brucebotti]

I went and had the starter benched, it passed. I switched the starter relay with the blower motor relay, still nothing, I also did some resistence checks on the starter relay, and its good. I went and talked the my jeep dealership, he said this does not sound good. He walked me through every test I can do, I have done them all. He is thinking the PCM might have lost ground and fried itself. $900. YAY not. So I guess monday I will have it towed down there. Maybe its time to trade it in. 140k mileage.

Thanks for the replys, any other ideas?

I'm not sure if these will fit the bill, but ebay has a bunch of Libby computers for anywhere from $50-$300. Hope this helps.

http://shop.ebay.com/?_from=R40&_tr...ep+liberty+computer&_sacat=See-All-Categories

Bruce

 

[Dave]

As tjkj said, check the ASD relay.

It should be in the fuse box in front of the battery. That has to be a whole bunch cheaper than replacing the computer. Maybe try that first.

Dave

 

[XJeepin06]

I did switch the ASD and the low fan relay around... Same part number. didnt help, but i will go through the fsm and see if there is a test for the asd socket.

The delaer told me that 2004 was the crossover from jtec to the computer where it has to be reprogrammed to the new vechicle. So i dont know if mine is the new or old system. I guess I could check the part numbers.

Other than the asd and the inner fender where does the PCM get ground? Also anyone know if the is a way to check the PCM for power? The fsm just says hook it up to the dealers test thing. I have to say my XJ is a whole lot easier to work on.

Thanks Again
Kevin

 

[kb0nly]

I did switch the ASD and the low fan relay around... Same part number. didnt help, but i will go through the fsm and see if there is a test for the asd socket.

The delaer told me that 2004 was the crossover from jtec to the computer where it has to be reprogrammed to the new vechicle. So i dont know if mine is the new or old system. I guess I could check the part numbers.

Other than the asd and the inner fender where does the PCM get ground? Also anyone know if the is a way to check the PCM for power? The fsm just says hook it up to the dealers test thing. I have to say my XJ is a whole lot easier to work on.

Thanks Again
Kevin

If you know someone with an OBDII code reader hook that up to the diagnostic port on the dash, turn the key on, and see if your code reader can communicate with the PCM. A failure to read could mean a few things, a failed computer, a bad ground, no power to it, but it would tell you that you have a PCM problem at least.

 

[XJeepin06]

If you know someone with an OBDII code reader hook that up to the diagnostic port on the dash, turn the key on, and see if your code reader can communicate with the PCM. A failure to read could mean a few things, a failed computer, a bad ground, no power to it, but it would tell you that you have a PCM problem at least.

I own a obd2 reader that was one of my first steps, (i guess I forgot to mention that). But when I hook up to the computer it comes up with a error. I have power to the obd2 port though. I am convinced that this is the computer. I guess when I shorted the 12v constant wire for the radio it fried more than just the fuse. I think I will try the ebay computers. roughly $300 and they program it to my VIN and mileage. They also say I can return it. Or should I tow it to the jeep dealership to have them diagnose it?

Kevin

 

[kb0nly]

I don't see how you could have fried the PCM by shorting that wire, the fuse should have popped and thats it.

There must be something else fried yet if you can't communicate with the PCM. The power to the OBD II port is seperate from the power to the PCM though looking at my 03' service manual.

Have you checked and verified every fuse in the inside and the underhood fuse/relay boxes? I would check and double check before spending cash on a PCM just to be sure.

Everything else comes on when you turn on the key, including the stereo?

 

[XJeepin06]

Yep everything works. I have triple checked and had my neighbor also check. Hell I even pulled all the fuses/relays out of my XJ to swap and nothing. I looked at the fsm, and I have tested all the connections for continuity. Its all there. The power from the ignition switch goes to the pcm, but all the test show that there is nothing after that.

Like I said I have done many radios and have poped a few fuses in the process but I have yet to have a problem like this.

Thanks for the help
Kevin

 

[kb0nly]

Yep everything works. I have triple checked and had my neighbor also check. Hell I even pulled all the fuses/relays out of my XJ to swap and nothing. I looked at the fsm, and I have tested all the connections for continuity. Its all there. The power from the ignition switch goes to the pcm, but all the test show that there is nothing after that.

Like I said I have done many radios and have poped a few fuses in the process but I have yet to have a problem like this.

Thanks for the help
Kevin

Damn.. Well sounds like a dead PCM then.

 

[kj924]

That really sux about the alleged PCM problem.

Just re-read your OP, gotta ask a question . When you installed the replacement head unit, did you use an adapter to the OE plug?

 

[XJeepin06]

That really sux about the alleged PCM problem.

Just re-read your OP, gotta ask a question . When you installed the replacement head unit, did you use an adapter to the OE plug?

When we purchased the vehicle it had a crappy kenwood, and I used the same wiring harness. Yes it is a plug into OE harness. No mutilation of the factory harness.

 

[JeepJeepster]

Doesnt help now and Im sure you know this but its always a good idea to unhook the battery.

 

[kb0nly]

That really sux about the alleged PCM problem.

Just re-read your OP, gotta ask a question . When you installed the replacement head unit, did you use an adapter to the OE plug?

Me thinks your fishing here??

Could something have possibly been hooked up wrong that would kill the PCM??

 

[michaelcubsfan]

I am having the same exact problem with my 04 Liberty. Please let me know what you find. I have changed computers (with matching skim module, key etc) have another to try tomorrow but I just don't think its the computer. Checked codes and computer sends nothing to the scanner!! Where does computer ground?? Help

 

[Billwill]

I am having the same exact problem with my 04 Liberty. Please let me know what you find. I have changed computers (with matching skim module, key etc) have another to try tomorrow but I just don't think its the computer. Checked codes and computer sends nothing to the scanner!! Where does computer ground?? Help

What exactly is your problem?

Engine does not crank?
Engine cranks but does not fire?
Starts in Neutral but not in Park?
Are you getting spark/Fuel?:emotions34: