2006 TJ no start and no crank

[Orange Jeepius]

I was driving down the road the other day when suddenly my jeep just shut off as if someone turned the key off and pulled it out mid-drive. Since then I have been unable to start it. It was towed home. I can turn my key to ON and it lights up and beeps at me like normal. When I try and turn the ignition absolutely nothing happens.

I've had a similar issue in the past where the Ignition Actuator Pin broke that gave similar problems. I checked that pin and it was still together and in working condition. I went ahead and replaced it anyway as well as the ignition switch itself. Still nothing happens when I turn the key to start. I do hear a clicking relay behind my glove compartment when I turn the key but nothing else. Not even the starter attempts to work, but I was able to confirm the starter is getting power and will crank if I jump it.

I have checked all fuses and relays and tried new ones for anything related to the starter or ignition and nothing changes. I turn the key and nothing happens. I'm at a loss as to what to look for at this point. The most baffling thing is why it turned off mid-drive.

4.0L I6 - Automatic

Any help is appreciated.

 

[macleanflood]

Do you hear the fuel pump hum when you turn the key to run?

Any fuel pressure? Harder to check with yours without a Shrader valve on the rail.

-Mac

 

[Orange Jeepius]

Oh, I do not hear the fuel pump hum.

 

[JKP]

Did you check the ASD relay, fuse?

If you turn the key on, off, on, off on quickly, does the PCM display any codes, then done, in the odo? 06 PCMs are known to fail.

A bad fuel pump won't prevent it from cranking.

Did you try starting it in N? A bad N safety switch will prevent it from cranking and sometimes they will start in N if not in P.

 

[Orange Jeepius]

I've tried starting in N and no dice. Just checked the ASD fuse and it's blown. This would indicate a short somewhere, no?

 

[JKP]

Not necessarily, sometimes they get old and blow.

 

[Orange Jeepius]

Tried a new fuse and relay and when I turned the key it attempted to start and promptly blew the new fuse.

 

[JKP]

Time to start looking for chaffed wires.

Check over dipstick, behind valve cover first.

 

[Jeepoftheseus]

It can only be three things: fuel, air or spark. The bad fuse makes me think there's an issue in your wiring harness that connects the battery to the starter, the alternator, the fuse box, and to ground. It's a pretty simple procedure to pull out the harness and take a look. I'd start by taking look at all of the ground connections.

I recently installed the jeep cables big 7 power cables. I forgot to tighten one of the ground wires. I hit a speed bump in my complex and the jeep died, but the accessories all stayed on. Luckily I cranked it right back over and everything was fine. I found the loose ground cable and tightened it.

 

[hear]

@Jeepoftheseus : excellent username.

 

[Painfultruth]

Tried a new fuse and relay and when I turned the key it attempted to start and promptly blew the new fuse.

Look at the O2 sensors.

 

[Orange Jeepius]

Thanks for all the help, I'll look into where this short is when i have time and light. Hopefully by Thursday.

 

[Orange Jeepius]

I would imagine this is problematic..

This is the O2 sensor for downstream rear I believe. Those copper bits were touching together.

 

[Jeepoftheseus]

@Painfultruth nailed it.

 

[Orange Jeepius]

Look at the O2 sensors.

First sensor I looked at. You're a savant.

 

[Orange Jeepius]

Well, i taped it up and replaced the fuse and it popped after 2-3 cranks again. Should I just be replacing the whole sensor before trying the fuse and starting again?

 

[Jeepoftheseus]

Well, i taped it up and replaced the fuse and it popped after 2-3 cranks again. Should I just be replacing the whole sensor before trying the fuse and starting again?

I don't think the sensor would be the problem, but I don't know a lot about them. My guess would be you have another short somewhere.

 

[hear]

If you found that on the first bit of wiring you looked at, I'm certain the rest is perfectly fine.

/s

 

[Painfultruth]

I don't think the sensor would be the problem, but I don't know a lot about them. My guess would be you have another short somewhere.

 

[Orange Jeepius]

After some further troubleshooting it looks like my ignition coil pack is bad. I was able to unplug it, put a new fuse in the ASD fuse spot and I can crank for days now and the fuse does not pop. All wires to that coil pack appear fine.