Bit of a story to tell here, please bear with me...

So I had the tranny go out on my NAS 2008 SC last year and replaced it, (after trying a rebuilt mechatronic first, which I kept in the "new" tranny), but after a few months had worsening hesitation/slippage/whatever in gears 3 and/or 4 which has been getting worse and does genuinely seem like the replacement tranny is failing as well.

However...

As I was troubleshooting/confirming that a few weeks ago, I read an article where somebody had similar symptoms and it turned out to be a power problem.
Alternator (still) seemed fine then but the battery was old so I replaced it but it made no difference. Then I started getting real transmission errors at the console a couple days ago and figured it was just the tranny being unhappy because of the slippage.

But just to be sure I used my IID tool to pull the diagnostics to see if there was anything useful, and saw all the errors below, which I assumed to be related to my changing the battery. But I did a video just to be on the safe side, cleared them all so I could get a fresh set of diags for the next round of errors and kept driving it.

Of course I got a few more errors but before I took the time to run diags again the engine cut out without warning as I was getting onto the freeway. I also got tons of warning lights flashing and bells ringing and a stream of errors across the console.
I coasted to the end of the onramp where it was wider, hopped out with my multi-meter thinking maybe I'd neglected to tighten a battery clamp or the alternator really had died or something, but battery voltage at rest was 12.2v, clamps and cables seemed fine, so just for the heck of it I tried the key and it started right up! Lots of warnings and flashing lights for everything and such still of course, but the engine was running! For about 2sec, then it stopped again, but I tried again, revved it a bit and then it stayed running and seemed to idle fine and things seemed okay aside from all the alerts.

At this point I had also plugged in the IID again and could see the alternator putting out 14.2v. I didn't take the time to pull the codes then (dammit!) as I was running late for a meeting.

So then...

After the meeting I came out and tried to run diags, but the IID tool is very picky and, among other things requires the engine to be running. Turning the key enabled all the lights and warnings but nothing at all happened when I tried to start the engine, not even a relay click. So I left it an hour or two, tried again, still nothing. I disconnected the battery for 20min or so, reconnected and tried again, still nothing. Quite literally a case of, "lights are on but nobody's home!"

That's when we towed it... a-a-and the mechanic says none of their diagnostic tools will even recognize that the CAN bus is present! I get the feeling "something" is choking the CAN, (and maybe even causing my original tranny issues?)


Looking for thoughts on getting the IID tool to work w/engine off, and how to troubleshoot the CAN bus, e.g. what can I disconnect to get it to the simplest operational state?


For what it's worth, this is exactly what I got from the diags last weekend, (transcribed from the video I took).
Power and random misc are probably from the battery swap, but the comm errors are interesting:

For starters I would confirm that the new battery isn't a dud, perhaps by checking the voltage without the engine running then switch on the headlights to see if the voltage drops well away or only a little.

Quote:

For starters I would confirm that the new battery isn't a dud, perhaps by checking the voltage without the engine running then switch on the headlights to see if the voltage drops well away or only a little.

Does you IIDTool not read codes with the ignition on but the engine not started? If it doesn't then I wonder if no power is getting to the ECM which usually powers the HS can-bus and being the same cause for the failure to continue running or not attempting to start. It seems as though it could be a basic power problem, possibly due to a loose fusible link in the engine bay fuse panel or a loose earth stud that is used by the ECM.
I have a wiring diagram for my MY12 TDV8 but there could be significant differences between MY07-09 and MY10-12.

a similar issue happened to me

https://www.fullfatrr.com/forum/topic51475.html

Hi, Worth speaking to Pat at Gap, he should be able to help you to get the IID to work with just the ignition on...

Battery voltage under 12.4v is considered discharged, the voltage should be over 12.6v after the battery has settled following a charge...

I would start with the basics and remove and clean battery leads even if they look OK, then do the same for all the earths you can find...

Good luck and keep us posted... Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

SoggyBottoms wrote:

a similar issue happened to me

https://www.fullfatrr.com/forum/topic51475.html

Oh, wow, that seems super-similar! And I didn't know about the CCF reset function in the IID tool, that could be extremely helpful!  2008 SC L322
2001 P38, Epsom Green, fully restored SOLD

GraemeS wrote:

Does you IIDTool not read codes with the ignition on but the engine not started? If it doesn't then I wonder if no power is getting to the ECM which usually powers the HS can-bus and being the same cause for the failure to continue running or not attempting to start.

Haylands wrote:

Hi, Worth speaking to Pat at Gap, he should be able to help you to get the IID to work with just the ignition on...

Could just be user error, I'm going to check the power and read the manual before I bother him.

Haylands wrote:

Battery voltage under 12.4v is considered discharged, the voltage should be over 12.6v after the battery has settled following a charge...

I would start with the basics and remove and clean battery leads even if they look OK, then do the same for all the earths you can find...

Good luck and keep us posted...

I know Rangies are voltage sensitive, didn't realize that much! (Guess I've always been lucky!) Will check voltage more properly today.  2008 SC L322
2001 P38, Epsom Green, fully restored SOLD

So it took a little longer, (busy, busy!), but we've got power at 12.6v and good grounds all the way around. We also discovered that once in awhile the CAN bus will work for a few minutes! And when it dies there's a burst of crap data on the line but we can't tell from what device.
Anybody got a CAN bus troubleshooting flowchart or something like that? Even just knowing the bare minimum of which devices are required to operate would be a huge help!  2008 SC L322
2001 P38, Epsom Green, fully restored SOLD

I had written that the TCCM was a HS can-bus gateway which it is for D3s & D4s but it is just another module in parallel on my MY12 L322. Hence I don't have any knowledge of your MY08 L322.

Here's the HS diagram for MY10-12 in case its of any help.

https://www.fullfatrr.com/gallery/albums/u...0Speed.pdf

Quote:

Here's the HS diagram for MY10-12 in case its of any help.

Thanks Graeme, even if it's not a match it'll give me key words for searching!  2008 SC L322
2001 P38, Epsom Green, fully restored SOLD

After unplugging 10+ easy-to-reach devices on the CAN bus it's looking like the instrument cluster may be the culprit!

Will update once that's confirmed either way, but in the meantime does anybody know of a reliable cluster repair/rebuild service?  2008 SC L322
2001 P38, Epsom Green, fully restored SOLD

Cluster is definitely the cause of the CAN bus issues. After some reading it sounded like they could be reprogrammed so got a good unit off fleaBay only to find that the SuperCharged are apparently "special" and not reprogrammable. (Dealer said it was hit or miss, sadly this one was a miss.)

Stealer wants $1400 for a new unit!

Anybody know of a reliable instrument cluster repair service in America?  2008 SC L322
2001 P38, Epsom Green, fully restored SOLD

Small addendum for those following along or finding this later. While it is true that the Instrument cluster was the cause of the CAN bus issues, the actual root cause was the ignition switch sending voltage spikes to the cluster and frying it. Apparently this is a rare problem but known to happen in this model series. 2008 SC L322
2001 P38, Epsom Green, fully restored SOLD