L322 can bus errors

i dropped lucky on friday and bought a 2nd hand allcomms off eBay for a bargain price, so i decided to also purchase a hp stream 8 so i don't need laptop to run it, anyway thats another story.

i've had a suspension/ABS fault for months, randomly happens and sometimes clears however using hawkeye i couldn't get to the real fault.
i've just been right through all the fault codes and cleared everything, so i'll see whats come back in a few days, but what i did find strange was i couldn't access fault codes on the LCM but i could access to change settings, the other thing i found in the air suspension, instrument pack and ABS there were can bus errors relating to the transfer box, the transfer box had about 10 error codes for different things, thats got me thinking dodgy connection maybe? i do occasionally start the car and it flashes up high range in the instrument pack when nothing has been touched.

any ideas?

A common weak point on the L322 is the transfer shift motor switch pack....overtime they become brittle and the casing starts to crack and fail....causing spurious fault messages and Trans Failsafe Prog messages.

Trouble is the switch pack isn't available separately and the whole motor assembly is sodding expensive.

The CANbus ties a few system together so a fault in one will appear in the other systems tied to the same bus.

The LCM being mounted on the Drivers Side A Pillar, can suffer from moisture....pop the lower side panel off (the one with the bonnet release) and have a look and feel around the LCM (it is half tucked up under the side of the dash) for any signs of moisture.

Sometimes, failure of the headlamp levelling ECU (passenger side A pillar, white box about the size of a pocket of cigarettes) can lead to difficulties reading some systems on the car.....unplug this and see if comms comes back to the LCM.

Cool I'll take a look I think I managed to communicate with headlight level Ecu, I also check both hids strange fault on both battery voltage <7.5v

RRkev said:

Cool I'll take a look I think I managed to communicate with headlight level Ecu, I also check both hids strange fault on both battery voltage <7.5v

Click to expand...

that is a common and spurious fault that can be ignored...I have that too.

So as there is jack all on tv I took the car for a 20 mile run and rechecked error codes :-
I can access and read codes on headlight levelling it was clear.
I still can't access LCM error codes with allcoms but I can change settings, I tried a debug that also failed
I can read error codes with navcoder though (even though they are just a string of numbers/letters) and clear them

After my run I had 3 error codes one relating to cooling map ( I have thermostat mod fitted)
Lambda control adaption per ignition fault bank 1 (this is a new one that won't clear, Hawkeye dosen't read this error either)

And on the instrument pack EBV function fault received from ABS ECU

EBV fault can be ignored, it is not fitted to the L322 (it is a carry over from the BMW uses).

Lambda Control Adaption fault is a new one on me....do you have the MIL lamp illuminated? if not, I wouldn't be overly concerned...if the MIL is lit and won't go out, then it is time to look at the lambda sensors and their wiring!

Unplug the headlamp levelling ECU and see if you can connect to the LCM.

no the MIL isn't on luckily according to the LR manual and it's lost me, it means adaption per ignition is to big or to small

If you have a generic OBDII scanner like an ELM327 or similar....using the free EasyOBDII software you can reset the fuel trim adaptions and see where you go from there.

The Adaptions are the trims the ECU makes to fueling based on sensor readings and engine performance data. It has long and short term trims.....when the long term trims start heading towards their top or bottom ends of the scale, you get fuel trim errors (or adaption errors).....

Here is a little bed time reading for you, it is based on the E39 5'er but it is essentially the same engine and system so will give you an idea on how it all works!

that's great cheers saint, i've also found online the error can be caused by the pcv hoses but usually the mil light will be on, think i'll check mine tomorrow just to be sure

ok so this mornings progress,i've pulled the headlight levelling module disconnected it, i checked the unit over and even opened it and pulled the board out, there looks to be no water damage and no green slime in the connectors. but i still can't access the LCM with allcomms, i open a session and it times out trying to read LCM info.
with navcoder i can access the info, and it's telling me there are 3 codes stored in the LCM but it errors when i try to clear them it does say my LCM is november 2002 build and is the original unit looking at the chassis number coded in.

with both navcoder & allcomms i can program the LCM functions (DRL,Headlamp Delay etc)

i tried to do a debug on the LCM with allcomms and that failed saying the K Bus is down although i can access every other unit on the KBus and read/clear codes, i think my next move it to try my spare LCM tomorrow when i have the day off and see if i can access anything with that connected and take it from there. i know RSW has a video posted saying to check fuses to all the major modules but as i can access everything except the LCM i think that maybe the place to start.

on the fuel adaption fault i've plugged in hawkeye this morning and checked the live data that is giving me bmix of 1.29 on one bank and 2.6 on the other it could possibly be a vac leak or a maf fault but i'll look into it more tomorrow when i have time ( the car is running fine at the moment) long shot but i haven't changed the spark plugs for a while i bought 60,000 mile Bosch multi point plugs last time that have been in just over 33,000 miles but running LPG they may have degraded.

Some more light reading.....gives details on BMW bus diagnostics and fault finding....

Possible vac leak or PCV valve fault as you say. Spray some brake cleaner around the intake manifold and see if the engine note changes.....this will indicate if the intake manifold has a leak somewhere

that will keep me busy

so i tried a different LCM today with the same results, i may drop an email to story and ask him about this.

the fuel adaptation fault has now cleared all i did yesterday before i left for work was reset the throttle pedal adaptions, drove it like i stole it to work and back and it's now cleared the fault, but no other codes have come back either which is a good thing.