no electronics in cabin, anti-skid, CEM,DEM, 2010 D5 awd m66

[nameuser]

Hi everyone,

I am new here.. I was hoping that some of you would be kind enough to share your wisdom, gut feeling and put me out of my misery. To give a full picture of the significant events in a chronological order to the faults popped up i managed to write quite a bedtime reading. We would be super grateful if you could give us some pointers.

I recently bought a 2010 xc 90 D5 awd (275) 183HP manual six speed for my wife.

It had some minor looking issues to begin with like
rear brake light message however the bulbs were fine,
rear view mirror high potentiometer but it still worked,
cabin temperature sensor no signal

and from the big boys league:
leaking oil at the camshaft seal,
swirl flap actuator rod kept detaching
some deep mechanical clanking noise when started from cold but it was gone in a few minutes.

Upon buying I changed the
timing belt
tensioner
water pump
fuel filter
brake pads
complete caliper rebuild
brake shoes
brake disks
antifreeze
power steering pump
gearbox fluid,
rear diff fluid no filter
engine oil+filter,
aux belt

The some new issues started to come up in the following order:
A few months ago the "change rear brake light" started coming up. I hit the side of the rear left lamp and it worked again. Still, I changed it, it was fine for a short drive and again it came back on the same drive. However the light was on.
I suspected it should be the brake pedal switch but I left it.
A few weeks ago the "anti-skid system service needed" message came up along with the "stop safely". My wife stopped and then the car didn't want to crank at all. A few mins later it stated again, anti skid issue was gone. And this happened once or twice more.
She said occasionally the clutch started slipping in 4,5,6th gear whilst driving, not even touching the clutch. Hmm, i thought a lovely crankshaft seal leak.. but there was no oil visible around the gearbox peep hole.
Then my wife was reversing uphill in a bumpy field with a loaded hose trailer and she mentioned "i really had to boot it". So the clutch started slipping more and more. Also the gearstick somehow lost its original position for only the 5the and 6th gears. The were a bit back from where they used to be.
Then next day all the electronics inside the cabin stopped working (apart from cabin light, horn, radio, flash, wiper, hazard), the car had the "battery saving mode" message. After a few tries with the key it started again. She thought the battery is flat so she drove around at high rpm for a bit and then the electronics worked again.
A few days later the same issue came up, with the twist: cabin light stayed on, rear lights stayed on even when they were switched off on the dash. I was away so my wife couldn't do much, she left the car as it was, battery went flat. She jumpstarted it, drove it around next day but none of the electronics came back. Then we noticed that this electronic issue happened both times after we had some really heavy rain...which might or mightn't have anything to do with it.

So, I just changed
the dmf,
the clutch
the slave cylinder
bevel gear oil BUT no sleeve collar due to time pressure. It still seem to engage but worn.
cleaned egr mixer and cooler and intake elbow which had massive amount of gunk in it.
charged the battery which had 12.6V in it after.
Wanted to test drive it and i let the car warm up while packed away. There was no clunky noise anymore with the new dmf and it was running much nicer. So in about 20minutes the car just stalled and i could not crank it. The battery went 11.5V. Swapped the battery, then it started. So i took for a test drive hooked on my vida.
alternator charge 0A constantly
SAS 0degrees constantly
cabin temperature sensor -236degrees celsius
abs sensors show identical speed on each wheel
DEM is grayed out
CEM BCM DDM are red in vida
At least the clutch is fine.

I took a voltage measurement on the alternator casing and it showed 11.62V at idle, at 1500 rpm 11.92V so i take my alternator is at fault. =)
A new one and a braker one are on order i fit the one that comes first as my wife is super desperate for the car..

Also in vida i have the following error codes:


BCM-0094 Communication between control units Communication problems with DEM
BCM-0100 Communication between control units Communicational problems with ECM
BCM-0115 Communication between control units Communicational problems with SAS, signal missing
BCM-0148 Communication between control units Wrong configuration ID
CCM-0040 Air quality sensor Internal fault
CEM-1A05 X-Power supply Signal too high
CEM-1A09 50-power supply Signal too high
DDM-0030 Rear view mirror potentiometer Faulty signal
DDM-0032 Rear view mirror potentiometer Faulty signal
ECM-500F Air condition - Faulty signal
ECM-6110 Engine cooling fan (FC) - Temperature too high
ECM-7600 Immobilizer - Signal missing
CEM-8F1D 15-feed or beam level control Shorted to supply
CEM-1A06 15-power supply Signal too low
ECM-4480 EGR position sensor - Faulty signal
ECM-6100 Engine cooling fan (FC) - Signal too low
ECM-6662 Glow relay control - Faulty signal
ECM-6664 Glow relay control - Faulty signal
ECM-683D Turbo control actuator - Signal missing
ECM-7700 Engine control module (ECM) - Incorrect check sum
PDM-E010 Control module Internal fault
SAS-0016 Control module Communication fault
SAS-0018 Control module Signal missing

I suspect the alternator is the main issue, the clock spring and potentially the brake pedal switch. I ordered these to be on the safe side.
Contemplating about the ignition switch too and tried to have a look at the CEM which seemed dry as much as i could assess it in situ (bottom half of the casing basically).


I never done volvos before and have no type knowledge at all just reading the forums.

Is there something that shouts clear at you but i don't see yet?


I guess i need a PCV kit too very soon.

Anyhow, thank you for reading it.

[scot850]

When these cars are not charging correctly and especially when the voltage is <12V, they start to through phantom codes. Make sure the alternator is charging in the 13.6-14.2V range ideally, a little lower is ok.

If you are not getting that it will though the low battery warning and a bunch of codes.

If the charging system and battery are all ok, then let us know.

Neil.

[nameuser]

Thank you scot850,



Well, it turned out i had a CEM water leak on the top. I just got back a cloned CEM an now everything works apart from the damn alternator. Hooked up to vida the alternator current is still 0A, 0V.

When measured on the alternator terminal and casing it still shows 11.70V which is i guess just the battery voltage and the alternator doesn't charge.



I already cleaned all the ground and positive terminals on the car.. put an other used alternator in which was tested okay before, tried a fully charged battery, checked all fuses but still nothing.



I have now a new fault code though:

ECM 6200 ALTERNATOR SIGNAL MISSING.



and the old ones obviously:

CEM 1C05 30-POWER SUPPLY SIGNAL TOO LOW

ECM 6662 GLOW PLUG RELAY CONTROL - FAULTY SIGNALDDM-0032 REAR VIEW MIRROR POTENTIOMETER FAULTY SIGNAL

CCM-0040 AIR QUALITY SENSOR INTERNAL FAULT



I have now cleaned the DELPHI plug which was soaked on the CEM as the plug also seemed to have some oxides on the outside. I used a very thin needle (super gently) and electric contact spray. Still the same alternator issue. No charging.





Do you guys have a suggestion what could this be, what should i move onto?

[nameuser]

If someone still reading =)

I checked the alternator's signal wire to the ECM A88 pin, it shows continuity. Measured the voltage on the signal wire whilst the car was idling, it is 8.52V.
So, that would suggest to me the LIN is up and running.

As far as i understand, if the CEM, or the ECM would be still faulty, i shouldn't have the LIN up and running. The alternator is a used one "reconditioned" allegedly. I tested it with new battery and cleaned all grounds around the car.
Tensioner is good, belt is good.

I can not think of anything else but that my replacement alternator is faulty and my original alternator wasn't necessarily faulty, just the water damaged cem shorted the LIN. Or that was also faulty..

Or am i missing something? Shall i take the "C" connector (Delphi) from the CEM apart and check the crimped socket in the plug as those were oxidated too? Although i cleaned it i can't be sure how good it is.. but then the LIN wouldn't work if that was the issue.. .agggr. Someone please put me out of my misery..
I visited 4 car electric garages today 3 of them said they could have not done more. Third one said it's a nasty one and gave me an appointment for September.

[nameuser]

Well, it was the reconditioned alternator. It wasn't reconditioned. Now i have alternator charge again =)

[abscate]

I’ve been on travel, but new parts can’t be trusted until they have been tested in these dark days

[brobert]

Maybe this information can help someone down the road:

Here's a scope screen shot of the LIN bus (taken at my V70 alternator).
If you see this activity, chances are that your CEM harness and plug are fine.
Of course your alternator might NOT be responding to the CEM, which is another issue.
I've never decoded the LIN bus but found the following patterns:
3 Large repetitive pulses on the LIN bus indicate BAD communications
2 Large repetitive pulses on the LIN bus indicate communications OK

VIDA also has an alternator test that will request various charging voltages.
You can find this test when the CEM is selected in the VIDA network diagram.
If the car's voltage changes in steps (cigarette lighter is handy for monitoring), things are good.