Grand Cherokee WJ - Failing to start

[gadgetgricey]

Anyone got any experience with these.

 

Has been fine for months, just paid a fair bit to get its through its MOT as all four of the struts underneath had surface rust, but now wont start.

 

Driven daily, parked up Saturday evening but refused to start on Sunday.

Turns over but refuses to catch.

 

Done a search on interwebs and loads of responses from the PCM (Power Control Module, I think) to SKIS (The Jeep Immobiliser)

 

Leaving work early today to try and have a gander, wondered if anyone had any experience on these.

 

Cheers

Dave

[Robson3022]

Worth changing the battery in your immobiliser fob (or give it a bite) I had this problem with mine and that fixed it!!

[gadgetgricey]

Worth changing the battery in your immobiliser fob (or give it a bite) I had this problem with mine and that fixed it!!

 

Have a key and fob (well 2 keys and two fobs)

 

Both fobs are working fine and lock/unlock the car as required.

 

However all for easy stuff first, so will get a couple of batteries on the way home.

 

Cheers

[Robson3022]

Mine did the same but for some reason a fresh battery fixed it!!

[gadgetgricey]

No luck with the new batteries

[NorfolkNWeigh]

If somethings turning over I usually give it a sniff of the Easystart can. If it try's to run on that , it usually points to a fuel issue.

[KruJoe]

Assuming it's a dizzle, have you pulled the glow plugs and bench tested them?

[gadgetgricey]

Turns out was a fuse on the PCM, so a really small 10A was stopping everything.

 

Got a couple in the car to keep me mobile , just in case it happens again, but worried why it happened in the first place.

 

Least its running again though

[SiC]

How has it failed? Blown with scorch marks? Or just a small blow and most of the fuse wire remain?

 

Fuse could have just failed from being weak and vibration.

[gadgetgricey]

Done a bit more checking and forced it to fail partially today.

Fuse not blown but thrown an engine code.

 

One of the other forums mentioned that the O2 lambda sensor could be at fault. Looks as though that's what is happening. Engine code says that O2 sensor reading too high. Looks as though when engine is rev'd hard O2 level reading spikes and either throws code or as the other day, blows the fuse to protect the PCM.

 

Removing the sensor the weekend and fixing / replacing as required.

[SiC]

O2 heater shorted out internally to the sensing element?