Diagnostic System failures...confused!!

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
miskin said:
Hi Saint.V8, I'm not sure if this will make you feel better, but I have EXACTLY same problem - my left xenon bulb (my car is LHD) exploded causing same "light effects" on instrument panel. These effects disappeared when I disconnected left headlight and were gone when bulb was replaced. Since that time I am not able to connect to diagnostics neither with Allcomms nor with official dealer's testbook or other serviceman's diagnostic system (I am not sure which brand it was). I am able to connect to engine and transmission ECUs via standard OBDII tools.
I, too, randomly receive ABS/HDC/... fault that disappears after engine is turned off. Probably it is not good news, but I am afraid it is not your allcomms that is broken.
I am not a pro like you and I was not able to have this fixed for almost a year, but if I could help anyhow, just let me know. I'd be so happy to find out what the problem is.
Click to expand...
Cheers Miskin, glad to hear it is not just me who has had this issue...and also glad to hear it may not be the All Comms.

My next step when I pluck up the courage is to remove the LCM and try again.

The LCM acts as a 'Master' on one of the diagnostic buses...similarly the Instrument Pack does too, mine behaves 100% until you turn the lights on, then it will fault out again...so I can only assume it is the LCM causing grief.

Trouble is, it is half buried under the side of the dash and will require the side of the dash to come out to gain full access.

Just got to get courage to remove the trim...I am OK with nuts bolts and washers...but trim and fiddly fasteners are not really my strong point.

Once I have taken the LCM out and check again, I'll give an update!
 
Hi, it wasn't really big PITA in my car to check LCM (on LHD, it's on passenger side under the glove box, isn't it?). It was my first hope, as I read on forums that this tend to get wet and cause diagnostics malfunction. But it didn't help in my case - anyway, I will check it again just to be sure.

When I was recalling what I did and what could cause this issue, I thought about few things. Too many things happened at the same time, but shortly, my expansion tank started to leak heavily and I replaced it. I just had brake pads and discs replaced and I wanted to get rid of "replace pads error". I did "reset all" via instrument cluster and then I did not see any error in allcomms (but I remember it was rather fast to read…). Next day I started car, turned lights on and that's when I first noticed light show on IP. I turned everything off and checked with allcomms if there is any log entry, but I noticed that as soon as I start to read from any ECU, it went to "error" on bottom right.
I thought I could break something with "reset all", which is related to instrument panel - gateway to diagnostics network, but it really makes more sense that it was some high voltage leaking to instrument panel that caused the problem.
One stupid question: Is it possible to somehow bypass instrument panel and connect allcomms directly to any single ECU? I mean, is the bus peer-to-peer, or is there master (IP I guess) required for communication?
 
miskin said:
Hi, it wasn't really big PITA in my car to check LCM (on LHD, it's on passenger side under the glove box, isn't it?). It was my first hope, as I read on forums that this tend to get wet and cause diagnostics malfunction. But it didn't help in my case - anyway, I will check it again just to be sure.

When I was recalling what I did and what could cause this issue, I thought about few things. Too many things happened at the same time, but shortly, my expansion tank started to leak heavily and I replaced it. I just had brake pads and discs replaced and I wanted to get rid of "replace pads error". I did "reset all" via instrument cluster and then I did not see any error in allcomms (but I remember it was rather fast to read…). Next day I started car, turned lights on and that's when I first noticed light show on IP. I turned everything off and checked with allcomms if there is any log entry, but I noticed that as soon as I start to read from any ECU, it went to "error" on bottom right.
I thought I could break something with "reset all", which is related to instrument panel - gateway to diagnostics network, but it really makes more sense that it was some high voltage leaking to instrument panel that caused the problem.
One stupid question: Is it possible to somehow bypass instrument panel and connect allcomms directly to any single ECU? I mean, is the bus peer-to-peer, or is there master (IP I guess) required for communication?
Click to expand...
My thoughts are the same as yours.....a High Voltage spike has taken out the IP or LCM...

The IP is the gateway for all the Diagnostic buses...unfortunately as far as I know there is no way to bypass the IP.

The various buses operate in different ways, on the CAN the individual ECU's generate a line voltage and send information using this self induced line voltage....whereas on the K/I buses, the IP or LCM (one is master the other a backup) provide a line voltage and the various ECU's switch this line to 0V to provide the data signal....so if the IP or LCM goes down, there is no line voltage to communicate on....

What I don't get is, that the K/I Buses work fine as the car still functions perfectly well with all the various systems working harmoniously which makes me think the K/I and CAN buses are working correctly, it is just the Diagnostic Gateway through the IP is bust - leading me to think the IP is infact the culprit (OBDII diagnostic interface doesn't use the IP and directly connects to the Engine ECU and Gearbox ECU) but that is a pain to get at, even more so than the LCM...so I may aswell try to disconnect the LCM and see what happens from there!

I do see myself having to get a replacement IP I feel, but then there is the faff of getting it coded to the car!!!
 
Saint.V8 said:
What I don't get is, that the K/I Buses work fine as the car still functions perfectly well with all the various systems working harmoniously which makes me think the K/I and CAN buses are working correctly, it is just the Diagnostic Gateway through the IP is bust - leading me to think the IP is infact the culprit (OBDII diagnostic interface doesn't use the IP and directly connects to the Engine ECU and Gearbox ECU) but that is a pain to get at, even more so than the LCM...so I may aswell try to disconnect the LCM and see what happens from there!

I do see myself having to get a replacement IP I feel, but then there is the faff of getting it coded to the car!!!
Click to expand...

This is what I wanted to highlight, too. If there is problem with communication between sensors, air suspension goes off right away etc etc, and I've been driving almost for a year with this issue only to see ABS/HDC/EAS problem once in a while (I also attributed this to my old battery as it disappeared with hot weather and reappears when it gets cold). So it is either that only part of some ECU responsible for diagnostics network is broken, or that the gateway is not working, because ECUs seem to be fine.
 
The fact that you got a Christmas lights display on the IP suggests to me it's the IP that took the hit. Will be interesting when you find out what has failed.
HID = hideous, what sort of engineeering is it when a blown bulb can take out other systems?
 
Datatek said:
The fact that you got a Christmas lights display on the IP suggests to me it's the IP that took the hit. Will be interesting when you find out what has failed.
HID = hideous, what sort of engineeering is it when a blown bulb can take out other systems?
Click to expand...

I do think you are right...the IP took a hit which is causing the lack of Diagnostic connection as this is the interface gateway....but I also suspect the LCM took a blat as well as the ABS/HDC/EAS faults only appear when you turn the lights on...so I am thinking I will need to check/replace both!!

As you say, a stupid design if a blown lamp can render the Diagnostic useless and take out 2 key ECU's
 
Saint.V8 said:
I do think you are right...the IP took a hit which is causing the lack of Diagnostic connection as this is the interface gateway....but I also suspect the LCM took a blat as well as the ABS/HDC/EAS faults only appear when you turn the lights on...so I am thinking I will need to check/replace both!!

As you say, a stupid design if a blown lamp can render the Diagnostic useless and take out 2 key ECU's
Click to expand...
Sadly, no option but to swap bits to eliminate the root cause.
 
St.

Wow what a nightmare. if I can help let me know.

I have been away fixing a 1930 MG....they are a different problem..
 
OK, long time since I did an update, sorry....but I have not done much more to sort this out until now....

Purchased a S/H LCM from a company on ebizzle (have used them before and had no issues, unit came with 90 warranty etc)

Today I bit the bullet and pulled the old unit out and plugged the replacement in.

I knew I would get the 'Manipulation' indicator on the dash up as the official procedure is to use T4/Testbook to read the information stored on the IP and LCM, then swap the LCM over and write this information to the replacement LCM. This is done as the LCM is used to store VIN. Mileage and Service Indicator information as a backup for the IP.

As my L322 isn' talking to diagnostics, I had no choice but to just swap it over and suffer the Manipulation light, until such time I can go to a dealer and get them re-synced!

Anywho....while the LCM was disconnected I tried to connect via diagnostics...still no comms

Installed replacement LCM, and again still no comms....and also the Bells and Whistles still occur when you turn the lights on!

Feck Bugger Arse.....

It isn't the LCM that is causing my issue then!

Soooooo.....back to ebizzle and I purchase a S/H IP from our Forum Sponsor Emmots Of Colne....due to arrive next week, so will try that and see what occurs....

If that fails, I may have to resort to start stripping interior trim out to reach all the various ECUs and disconnect them in turn and see if I can get some sort of comms back....

The thing that makes me nervous is, after disconnecting ECUs, what happens if I get a fault message/code up and I still can't connect to diagnostics???

Guess I will cross that bridge when I get to it!

So, as for an update, still no further forward apart from a spare LCM and an IP on its way!
 
I feel your pain mate

What a nightmare your having


That's true about the faults, if you get a hard fault you won't be able to reset it !

Pretty sure you've tried it but have you connected a fault mate to the system and tried it ?
 
Hi Saint,
just a thought, our L322 didn't want to speak to the Faultmate. Turned out there's a fuse that controls it - the OBD I think - sorry can't remember exactly where, its in the book and it was a couple of years ago and I've slept since then.
 
i have a faultmate, but only works with my car but bbs may do a temporary swap to yours but i am guessing it would be 50 euros to yours and then 50 euros back to mine as they are both l322. That's the equivalent to 1 hour at a main dealer.
might be a last resort for you at some point mate

Remember, the pleasure from owning an L322 comes not from driving but from finally working out whats wrong with the little ****e and fixing it, until the next time ... :)
 
forthbridge said:
Hi Saint,
just a thought, our L322 didn't want to speak to the Faultmate. Turned out there's a fuse that controls it - the OBD I think - sorry can't remember exactly where, its in the book and it was a couple of years ago and I've slept since then.
Click to expand...

I have checked both Fuse 15 and Fuse 5 which feed Pins 1 and 16 on the OBD....I have 12V at both pins and also on Pins 4 and 5 I have a good earth connection!

Looking at the back of the OBD, there is no corrosion or loose wires...

Thanks for the advice though!
 
holidaychicken said:
i have a faultmate, but only works with my car but bbs may do a temporary swap to yours but i am guessing it would be 50 euros to yours and then 50 euros back to mine as they are both l322. That's the equivalent to 1 hour at a main dealer.
might be a last resort for you at some point mate

Remember, the pleasure from owning an L322 comes not from driving but from finally working out whats wrong with the little ****e and fixing it, until the next time ... :)
Click to expand...

Cheers Andy, may have to look into that if the IP swap is a bust!
 
no bother mate, i am guessing you have the info below already but i have the electronic library if you haven't. i think its for the L322

DIAGNOSTIC SOCKET
DESCRIPTION
General
The diagnostic socket is located behind an access panel on the drivers side of the fascia.
The socket is constructed to SAE directive J1962 standard and allows attachment of
TestBook or T4. The diagnostic socket allows detailed fault diagnosis checks to be carried
out on the vehicle via an ISO 9141 K Line Bus and the Diagnostic DS2 Bus.
OPERATION
Power Distribution
Feed from the positive battery terminal (C0192) is supplied to fuse 15 and fuse 53 of the
passenger compartment fuse box (C0632) on an R wire. Fuse 15 (C0586) provides a
constant battery feed to the diagnostic socket (C0040) on an RUY wire.
Fuse 53 (C0583) provides a constant battery feed to the ignition switch (C0099 on Td6
vehicles, C0028 on V8 vehicles) on an R wire. When the ignition switch is turned to the
'ignition' position, current flows across the switch (C0099 on Td6 vehicles, C0028 on V8
vehicles) to fuse 5 of the passenger compartment fuse box (C0585) on a G wire. Fuse 5
(C0587) provides an ignition feed to the diagnostic socket (C0040) on a GW wire. The
diagnostic socket (C0040) is earthed on a pair of NB wires.
K Line Bus
The following are connected to the diagnostic socket (C0040) via the K Line Bus on WP
wires:
 Transfer box ECU (C1319).
 ABS ECU (C0506).
 LH Xenon Lamp ECU (C0009).
 RH Xenon Lamp ECU (C0011).
 Steering angle sensor (C0862).
 Instrument pack (C0233).
Diagnostic DS2 Bus
The following are connected to the diagnostic socket (C0040) via the Diagnostic DS2 Bus:
 The V8 ECM (C0331) on WPY and B wires.
 The Td6 ECM (C0331) on WPY and B wires.
 The ZF automatic transmission ECU (C0932) on a WPY then WP wire.
 
Cheers Andy, I have checked the two +ve feeds to the OBD and also the two earths too....

I may just do a continuity checked between the K Bus line on the socket and one of the ECUs and see if there is any issues there!
 
may stir some ideas while you are there, have you got a copy of the electronics pdf mate with a map of what all the pins do and other stuff that is a bit over my head tbh
 
You must log in or register to reply here.

Similar threads

O
03 L322 EAS ECU Can bus fault / ABS temp system deactivation
Replies
1
Views
583
oldradiotech
O
I
0x0032 CAN bus Fault
2
Replies
22
Views
2K
invisible999
I
R
TüV problem in Germany
Replies
0
Views
235
roythebus
R
I
Fauls after reading with GAP IDD Tool - which one are 'real'?
Replies
19
Views
866
invisible999
I
Danil89Sever
L322 Problems with the ds2 bus (k-bus), I cannot change configurations and load them, there is no communication with the blocks.
Replies
4
Views
847
Graculus
Graculus
Back
Top