2011-2013 JGC 3L CRD volunteer

[Adrian2012]

Hi All,
I am hoping to find a volunteer to help me with a power problem with my 2012 Jeep Grand Cherokee 3.0 litre CRD. Anyone with a 2011-2013 model the same as mine could possibly help. My alternator burnt out and may have taken some power connections with it. Online diagrams, even the Jeep dealership and Jeep Australia, have not been accurate. So, I have been doing testing wire by wire, module by module. I suspect that my vehicle has lost a connection between the alternator and the battery. I would like someone to volunteer to conduct a test on their working vehicle. You may need to know the 4 digit security code for your radio before you begin
See attached photos for guides. First, disconnect the negative lead from the battery post and keep isolated. The battery is in a tub under the drivers seat after sliding the seat forward. Second, under the bonnet remove the red cap of the remote battery jump post, remove the 13mm nut and remove the lead and keep isolated. This is the lead direct from the battery to the jump post which has 5 large fuses in a fuse block underneath, which in turn takes battery power to other parts of the vehicle including to the PDC/TIPM. Thirdly, there is a black box behind the PDC/TIPM that is an Auxiliary PDC1 which also contains the DRL relays. There is a black cover over a post to the right of the box which needs to pop off and the 10mm nut removed and the lead removed and isolated. This lead comes directly from the alternator into the Aux PDC1 then through 4 x 50amp fuses that go to another Aux PDC2 over behind the airbox which in turn sends power to other components in particular the power to the PCM. Lastly, connect a DMM between the disconnected and isolated alternator cable and battery cable to see if there is a connection using the resistance/continuity setting. If the DMM remains at OL, like mine, then there is no direct connection elsewhere. I think you should find a connection which would provide a number of some sort to the DMM.
After the test, reassembly is simply the reverse order. No memory info will be lost, only the radio code might need to be entered, depends on the time taken.
Many thanks to anyone who can assist.
kind regards Adrian.

[FARWEST]

Adrian...try a PM to Mousie...he's a bit of an electrickery wizard...and treebreakerbob has owned his since new...he may have some ideas/info that can help...or maybe they'll see your thread...GOOD LUCK

ps: both are very cluey fellas...hope I havent offended either by dropping them in it

[Adrian2012]

Hi All,

Fixed the problems, Thanks for those that have contributed over the several threads I have had going. After the alternator burnt out and created a lot of smoke thought to be a fire at first when my wife was driving and I wasn't there, the firies came and put it out and disconnected the battery at the remote charge post. It turns out that there are two cables connected to the post and unfortunately they tucked one up under the brake master cylinder and made it look like a cable that went through the firewall. The insurance company hired a "forensic expert" who reconnected just the obvious cable and ran tests and concluded that the PCM had an internal fault. The insurance company denied the claim and concluded that it was wear and tear and cancelled my insurance as well stating that I had been untruthful and not declared a mechanical fault with the alternator. Months with the car at home replacing the alternator then the PCM then the TIPM and chasing can-bus faults throughout the modules leading me to trace all the wires myself because there were no accurate wiring diagrams anywhere and I had to take what was correct and work out the rest. So, I find that the PCM is not getting power. Tracing leads me to find two auxilliary PDC's with fuses and relays and a connection to the alternator, but no connection from the alternator to the battery. Just as I was about to peel back the harness I had a last look at where cables went and one that looked like it went into the cabin but I tugged on it and out comes this round flat connector that obviously went onto the remote charge post. I put it all back together, charged the battery and it started straight up and ran. My original PCM and TIPM were in place so nothing wrong with them either, just the alternator. Faaarrkkk. Fancy pulling off a cable and then tucking it away out of sight, you should always leave loose connections visible.

[Treebreakerbob]

I couldn’t find a clapping emoji but you deserve it for perseverance, me I am going to check tighten that connection as my vehicle MY13 suffers from an ecu/pcm reset every now and then. Code comes up but workshop manual says it?s nothing and to ignore it, only thing is I think it’s tied to my fuel rail pressure code as when resetting, power is discontinued momentarily and on a freeze frame readout of the code when the fault was set the fuel rail pressure is zero. The code is logged in the bcm in the drivers door module because that’s where Jeep assigned it to go

As drover said the best place to start looking for faults is on recent work or repairs, but you would have to know that the jump post wires were disconnected.

Again great work and perseverance

Bob

[drover]

Thats an amazing outcome, I looked at both manuals and pretty ordinary with the 11-13 having 2 connections at alternator and the 14-17 having 3 but very little to go on ................. How do things go now with the insurance mob, another battle I suppose ? ...

[Adrian2012]

Originally Posted by drover

Thats an amazing outcome, I looked at both manuals and pretty ordinary with the 11-13 having 2 connections at alternator and the 14-17 having 3 but very little to go on ................. How do things go now with the insurance mob, another battle I suppose ? ...

I moved to another insurance company. I explained the story and they were happy to cover me.

[bjm]

Have you tried claiming from FCA re alternator failure! Quite a few diesel owners have got the faulty burnt out ones replaced foc.Remember its the same alternator as in the 3.6 petrol GC that also burns out originally covered by a worldwide FCA safety recall.!