Gyrometer / Accelerometer sensor

[GiveMeABreak]

Hi Phil, thank you for your Forum donation. This will cover your for official parts requests for up to 2 years.

Please provide your VIN and I'll locate the part for you.

[kingjafad]

Thanks Marc - Just donated.
Vin is VF7**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Hi Phil

The Steering Wheel Angle Sensor is contained in the complete Comm 2008 unit shown at item (1):

Item (1) Switch Block Remote Control, part: 98072635ZD, £476.69 inc. VAT direct from Citroen.

There are some here on Autodoc:

https://www.autodoc.co.uk/car-parts/oem/98072635zd

But many places are sold out of these..... but at least you have the part number to search on.

[kingjafad]

Crikey! Ill be finding an Ebay spare as a backup plan and maybe taking the Comm2008 unit apart looking for dry joints/damaged cables etc (I played with comm2000's a while back).
Thanks anyway

[GiveMeABreak]

Just be very careful of the airbag of course I'm sure you know and also the clockspring as this can easily be damaged.

[kingjafad]

Thanks Marc - I have read the instructions for the airbag removal in DocBackup so will be careful.

May I ask some follow up questions please with the intent that once I've got my head around it, I may be able to support others on this forum too.
1. In SEDRE I see the ABS/ESP wiring as the following:

My intent is to see if i can trace wiring from the ABS module to the Steering Angle Sensor with my trust Multimeter/scope. But i am struggling to see if there are any wires specifically for the Angle Sensor. I assume the Com2008 unit is item 0004 in that picture? Any pointers for tracing the wiring please?

2. In DocBackup I see the Com2008 unit listed as about 5 different part numbers - How did you tie my VIN to the specific part number please? Is there somewhere in DocBackup that I can enter the specific VIN to narrow the part numbers returned?

For example, the only Com2008 unit in that screen showing it includes Steering Angle Sensor is 98072638ZD (admittedly its in the mass of text that could easily be overlooked) which then makes me wonder how the steering angle is measured on the other Com2008 units? (maybe separate sensor?).

Cheers,
Phil

[GiveMeABreak]

We don't use that Phil - that's on offline system made 9 years ago and no longer and by PSA. So no good today as there will be thousands of parts numbers that have been superseded / replaced now.

That is why we provide this as a service to donating members, as their own subscriptions would be expensive for timed access for the occasional benefit they would get. The old offline version you have does not work with VIN numbers.

The parts in your example are why we ask for the VIN, as the different systems, options and equipment unique to each vehicle will often mean having different control modules - the correct one is essential.

Regarding the Steering wheel angle sensor, I believe these are all multiplexed, so nothing much you can do there to be honest.

[wheeler]

. But i am struggling to see if there are any wires specifically for the Angle Sensor. I assume the Com2008 unit is item 0004 in that picture? Any pointers for tracing the wiring please?

No, 0004 is the instrument panel. AE00 is the electric steering lock. I cant actually see the comm unit in that diagram, the comm unit is normally component CV00.

[kingjafad]

I have ordered a warrantied 2nd hand Com2008 98072635ZD that will arrive next week (£150). I did notice all the ones available are ...ZD02 (not sure if thats the version increment number, i.e bug fix version as opposed to the original). I'll post an update once I get it fitted and tested for the benefit of others with the same symptoms as myself.

[kingjafad]

So.... short answer - It didnt fix it.
The com2008 unit ended up being exactly the same unit as fitted (98072635ZD01) - manufactured date about a week apart! So I had high hopes.
After the fiasco of my steering wheel not having the little holes in it for releasing the air bag (but once i did get the air bag out very carefully.... I put those holes in for next time) There is a couple of youtube clips of someone having the same drama. I ended up using a small allen key from behind the wheel to release the airbag.
Anyway the rest of changing the Com2008 unit was a doddle, put it all back together. Put it on diagbog, cleared the nifnaf codes from having had the battery disconnected. And then went to ABS/ESP Steering wheel angle sensor menu - still shows 780degrees and '???' for the top 3 items. I tried the calibration menu and it gave exactly the same message as before 'youve already started a calibration, so cannot continue'.
Everything else is the same as before - so still no error codes, but brakes are pulsing at all speeds as if it thinks its skidding.
So I resigned myself to changing the ABS module itself. And that is a pig to get my hand even to the connector. I Couldnt even get the connector off.
There seems to be an orange cover that lifts up a little to allow pushing a black clip which allows the release of the white lever which I can get it to move up and the whole plug seems to raise about 5mm with it suggesting its doing what its designed to do, but i am struggling to get the plug out of the connector and i dont want to break it by pulling too hard - I saw a bosch webside showing the pinouts for ESP9.0 and they look delicate . - admittedly my hand is a bit contorted to get in there.
Any ideas please?

[The extension zip has been deactivated and can no longer be displayed.]

[The extension zip has been deactivated and can no longer be displayed.]

Also one last thing, does anyone know where this clip is from please?

I found it loose at the bottom of the steering column on the carpet. Possibly unrelated to my changing the Com2008 as I didnt have anything drop/spring off that i noticed. USB is just for size comparison

Thanks in advance. Phil

[kingjafad]

So - a bit of an update -
1. I still havent been able to get the plug off the ABS module - (admittedly ordered one of ebay with the cable and plug in it so i can see how it comes off).
2. whilst i was waiting for that I learnt a few new bits in SEDRE wiring - I didnt realise, but clicking the MUX box in the diagram opened up a whole new avenue in tracing wiring for the Steering angle sensor. I have found CV00 and the 4 pin plug to the Com2008 module can be back probed to see whats on the CAN lines.

Now, I checked with a multimeter to find the ground wire (pin 3 - continuity to chassis) which should make pin 4 the 12v feed. However, my multimeter shows pin 1 to have 12V. - Its a flat 4 pin plug so if pin 3 is ground, the one next to it on the edge is definitely pin 4 (or is that an irrational assumption given french design )
I connected up a scope to the other two pins (2 and 4) and i get some signs of canbus square waves - I have not really figured out what settings are best yet for showing a reliable CAN signal - bit more research to be done there.(Unless one of you techie types knows the ms/v/pwm settings etc for a scope.)

Am I going crazy or is it possible that SEDRE wiring diagram is incorrect?


Update 12:17pm - Clearly i am losing my marbles - I just disconnected that plug and did a diagnostic scan - it cannot communicate with com2008 - so all lights, wipers, indicators etc didnt work - clearly that is not just the steering angle sensor plug and clearly it works for everything else so not the problem. However whilst i had it disconnected, i went back into ABS and Steering Angle parameter measurements and it showed the 780degress from the original problem (and that is with the Com2008 disconnected) so please correct me if i am being dumb but that points more toward the actual ABS module being the cause of the snag now.

[kingjafad]

Another update:
I finally figured out why i had such a pig of a time getting the abs module plug off - the last person snapped a tiny black tab at the top of the connector which meant that the cable cover with the white lever simply pushed up rather than levering itself away from the lugs that hold it in the module. It wasnt easy but once i had a scrappy module with a working cable cover on there, it was a piece of wee to get the connector on and off as it was designed.....

Anyway, I pulled some cable ties to allow the plug a bit more room so i could plug in my scrappy module and see if the Steering Angle Sensor problem went away (without going to the trouble of taking the original abs module out and bleeding everything.. just to test really). Well the SAS changed 8 degrees and needing calibrating, happy days or so i thought. Turns out this scrappy module was set for a grand picasso, with automatic gearbox and it was complaining of not being able to talk to the auto gearbox in my manual car and wont calibrate whilst its got fault codes outstanding! Ok, I'll just configure it with the right settings I took note of from the original - however diagbox keeps complaining that that it cannot contact the server when i try to configure the ABS ECU settings (or cannot connect to internet in other words). I checked whether that was the same on all ECU's but it isnt, my engine ECU seems to offer me the drop downs to change settings (i was too scared to commit to changing anything at that stage), so why does Diagbox not let me change configuration for the ABS module. May be time for a separate topic now, ill have a ponder.

[GiveMeABreak]

What version of Diagbox are you using? If V9.* then forget it as ECU telecoding can't be done without an internet connection to PSA servers an account, official software and payment.

[kingjafad]

Thanks for the confirmation Marc, I had since found several posts that you had pointed out telecoding started drifting out of diagbox after 7.57, so I have made a virtualbox machine with 7.57 and will give it a test on the car tomorrow. (Thankfully my C4 is 2013 so looks like it is supported) If I get the option to make changes to my existing ABS, then I may be in luck.
Again - cheers for the support.

[kingjafad]

Another update - so i got diagbox 7.57 to talk to the car and it allows me to get to change configuration page of ESP ECU but it strangely is not sure its ESP90 ecu (claims to be unrecognised) but then reads all the details fine. I made the changes to my test ESP ECU (correct gearbox, wheels etc) - original claims to have 'steering wheel angle estimator' rather than steering wheel angle sensor - not sure if thats correct or not but its the same on my original and the test one. When i came to save the changes (cog icon on the bottom right of the page) it fails 'Programming Failed Error (code 415)' . Any idea what that means? I connected my original one back in and just tested trying to alter the wheel size as a test of programming, it too failed with code 415.
I tried with diagbox 7.58 but that immediately wanted me to put username and account in for connecting to servers - so i guess 7.57 is the limit for me.
Just need to figure out what code 415 on programming means and I could be one step closer to my fix.
Am i supposed to go to pack repair and replace ECU (i started and it asked me for original ECU to copy counters from, I wasnt sure what would happen to my overall car health if i did that all the way so i stopped to ask here!.)
Any ideas - code 415, replace ECU menu?

Edit 1 - I also noticed on the Engine ECU that it is configured for ESP present, but ABS absent? Is that correct too?