No crank no start anti theft light

[ThGraham]

2005 jeep liberty

It has 67k miles on the frame. The engine was replaced when it had 35k miles on it in 2017. (Due to corrosion, apparently that was a common problem with this model, it was still under warranty so insurance from warranty covered engine and my rental costs.)

Now I have the anti theft light on steady, no start, no crank. The air bag lights come on in 5 seconds then the check engine light after another 5 seconds. Happened once and I pulled the skrim fuse left side driver #33. I put it back in and it ran good for two days. The anti theft red dot came back so fuse replaced and still same won’t start. Tried starting it in neutral and it started, turned it off and won’t start again, won’t start in neutral now. Ran computer obd2 and says not connected. It acts like the computer is dead.

Jumped ASD relay, starts fine. Tried a new ASD relay same thing. Drove it to dealership with jumper in to get the comp read. Their computer cannot read anything, PCM cannot connect to PCM. Ran it with ASD jumper in and no defects noted. They used an OBD and a larger computer, nothing would read. They told me that it should not start with the jumper in…..apparently they aren’t good mechanics.

I am thinking I have a bad PCM. The next few days I will pull the PCM and check all the wiring. Dealership was no help and just wanted to sell me new car.

Anyone have some suggestions? I have read a few on forums here but nothing matches up. I am used to doing wiring so I will dig in it but the wiring diagrams I have seen are not very good.

 

[KJowner]

If it's not cranking then you probably have a fault with the switch on the selector that prevents it starting in gear.
The loss of communication with the OBD port could be a fuse, broken wire, corrosion etc, it may be a PCM fault but I'd check the other bits first, especially as it runs OK.

 

[DadOSix]

Don’t forget to consider the ign switch actuator / broken pin scenario.
In a nutshell - key on, lites on, no crank, but you can jump the asd and get a successful start, the broken pin is a likely suspect. The broken pin does not allow the key to turn the switch all the way to start position.

See this to get started :
Thread 'Key ignition actuator'
https://www.jeepkj.com/threads/key-ignition-actuator.78834/

 

[ThGraham]

Don’t forget to consider the ign switch actuator / broken pin scenario.
In a nutshell - key on, lites on, no crank, but you can jump the asd and get a successful start, the broken pin is a likely suspect. The broken pin does not allow the key to turn the switch all the way to start position.

See this to get started :
Thread 'Key ignition actuator'
https://www.jeepkj.com/threads/key-ignition-actuator.78834/

I can turn the key and start it with the ASD relay jumped. The starter relay jumpered will get it to turn as soon as the jumper is installed. But the ASD relay will only start if I turn the key. So the key will start it, that is why I don’t think it is the key ignition actuator. The key ignition works and turns the car over. Everything works with the ASD jumped, I can even use my computer for codes but they all show up clean. I even put a low battery in to see if I would get a fault to see if the computer would read it. And it gave me the battery code p0562 Low voltage. With the ASD relay installed it goes into anti theft light and cannot connect to the PCM.

So I am scratching my head, the key will turn the car on and the computer will give codes only if the ASD is jumped. I did replace the ASD relay but it changed nothing. I am about to shoot the ASD wiring to see if that is where the problem lies because it is pointing to that direction.