Member Since: 01 Jun 2025
Location: UnderChassis
Posts: 4
D4 3.0 SDV6 - Fault help CAN Bus modules issue
Hi all,
I have a Discovery 4 2011 which will not run (Crank, starts very briefly, no throttle response, stalls). Having tested lots of things like fuel flow from LPFP etc, checked Cam Chains etc.. Wasn't really showing any faults on a generic code reader so didn't think much of it, but I got hold of SDD and read codes, and I note there is lots of module/communication related faults and also none of the modules at all on MS CAN are responding.
When the car broke down originally it was being used and cut out, as it hit a big bump in the road (which may or may not be related) and was recovered.
I have checked lots of things found on other threads like:
Earth on drivers side inner wheel arch (RHD) - gave a good tug and looks ok, tried adding jump lead just in case had no effect.
Large Connector passenger side rear wheel looks very clean inside
Having came across the above issues on the forums I was sure both times these would be the fault as symptoms other experienced seems close.
ODB port checks
HS CAN PIN (6 and 14) and MS CAN (3 and 11) are both showing 60ohm resistance when CAN is offline/idle.
Multi-meter (MM) - short to ground or Short to power
1) Does not show any voltage between any of the above PINs (3,6,11,14) and ground
2) Does show resistance although high 7K on (on 20K ohm setting) although this does seem to change each time i test - I don't know if this is just resistance through connected modules to ground? Or if it needs to worry about it.
CAN Network test on SDD seems to be able to query info from HS CAN modules but all the MS CAN modules show no info (I do not know if that is expected but suspect not, they seem to show green ticks as the tests run which is strange. They show red Xs on the main session screen for all modules.
I have disconnected the ECM behind battery and also ABS Module? Just towards from off car on drivers side from brake servo, and still get above resistance to ground on CAN lines. I just dont know if this is normal.
Faults are as follows:
There seems to be a couple of permanent DTCs and lots of others which come back after I try and start the vehicle.
After codes cleared the below remain:
Click image to enlarge
After attempting to start the below also appear,
Click image to enlarge
Dash seems to show (although these seem a bit random when fault cleared when they appear):
Emergency brake assist
HDC not available
Stability control not available
I have tried this with a good jumper pack and vehicle connected throughout to ensure good power source.
Any pointers would be really appreciated. This one has me stumped.
2nd Jun 2025 8:05 pm
discodave74
Member Since: 01 Jun 2025
Location: UnderChassis
Posts: 4
This is the SDD screen showing the modules not responding.
Click image to enlarge
Many Thanks again if anyone can help.
2nd Jun 2025 8:45 pm
discodave74
Member Since: 01 Jun 2025
Location: UnderChassis
Posts: 4
For others who may encounter similar issues reading modules on MS CAN. I have found out the interface I am using GODIAG D101 (J2534) does not support MS CAN, and therefore this is why none of those modules are showing as responding at least in SDD.
Also the 3 error codes displayed on the Dash I now realise appear after using the cable only, if I clear codes and disconnect it, they do not return on attempts to start. So these are not the issue, Emergency brake assist, HDC not available, Stability control not available
The issue remains I have a car which will not run, cranks, runs, then dies immediately after initially firing. I will try to get a cable which supports MS CAN to read with SDD.
Any other ideas which I could check to help locate the source of the issue. The vehicle will run on easy start so I have to an extent, excluded serious internal engine issue.
Cheers
3rd Jun 2025 7:19 pm
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 21023
You need to use a decent diag system, not a cheap cable and hacked software
You'll never be sure of what is genuine info, and what has been misinterpretedMy D3 Build Thread
Member Since: 01 Jun 2025
Location: UnderChassis
Posts: 4
Thanks disco-mikey, point taken.
I will try and find someone local who can help in Leicester area as car is currently not runnin/driveable.
I will also start a thread about the no start issue in the fault finding section.
4th Jun 2025 9:59 am
AustinJMJ
Member Since: 21 Nov 2024
Location: Leicestershire
Posts: 173
Perhaps, if you are suggesting that you are facing issues reading faults - with what Mikey said, perhaps something more comprehensive like a GAP Tool would be able to shed more light on the issue?All the best,
Austin
5th Jun 2025 6:03 pm
Grant-B
Member Since: 02 Apr 2025
Location: West Midlands, Tamworth
Posts: 173
Hi Disco Dave,
I have an iCarSoft scanner that finds most issues.... except those of the wife lol...
Depending on where you are, maybe i pop over & see what we can find ?
I am based at B76 9AF
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
