[DayvG]

So last night I changed my DSC pump for an ACC version. I followed ISTA with no issues. I injected a CAFD and VO coded then took it for a test run. As soon as I started braking I got a brake fault. I checked with ISTA and it was front and rear brake sensor. I checked my CBS and it returned brake pad service due 0 miles and was also not resettable in the KOMBI service menu. I then flashed the DSC to latest i-Level to match the car, cleared faults and the CBS was showing correct and green again with no fault. I started to drive and the fault returned and CBS showed 0 miles again.

I haven't had a chance to check but I can't imagine I have broken both brake sensor cables! Anyone sen this before and can offer some advice?

TIA

Dave

[danyro]

Hi

Please can you share with me/us briefly the steps that you did for replacing the DSC? Bleeding process etc?

thanks

[DayvG]

Yeah sure. Fully depressed brake pedal using a tool, removed wheel arch and trim. Disconnected brake lines to DSC, disconnected old DSC and fitted new one. Checked all connections were tight. Using a pressure/power bleeder I added new BMW DOT4 fluid, connected to reservoir and pressurised to just under 2 bar. I then bled the system starting at rear right, then rear left, front right then front left. Once clear and bubble free I checked the level in the power bleeder and ran the ISTA program for brake bleeding. On completion, checked reservoir level and put everything back together. I conducted the coding process prior to conducting the ISTA bleed program but flashed the ECU AFTER the bleed program.

Also On getting to the car this morning to drive to work the CBS was green again but was showing the incorrect mileage until next service was due. It was showing 3100 for front and rear. I'm sure this was at least 17000 on at least one of them. The second I start to drive the fault appears.

[danyro]

As I know, usage of brake pads are calculated by DSC ECU. in your case, i am almost sure that new fitted DSC contains info from the previous vehicle. And this is contradicting with the CBS stored in KOMBI.

I would initiate some CBS ABL functions from ISTA to check what is stored in CBS exactly. and also I would check ABL functions for DSC pump - you can get them via service menu-> body(if i recall right) in ista or via search function.

if you would broke the sensors cable, a clear error about sensors will appear - no sensor fitted or something like this

just my thoughts...

[DayvG]

Perfect, thank you. I will have a look when I get home. Does ISTA give the ability to amend/remove any service information or even completely remove stored information from a unit? I have read previously that the "Code default values" can be used in some instances and isn't necessarily as scary as we might think? (I'm not about to go and press it)

The positive part is i know my brake pads are fine and the brake system is functioning as expected albeit with the CBS/brake error present.

[danyro]

yes, with ista you can update/adjust CBS info and much more service functions. but you cannot delete the CBS data. in worst case scenario, you can reset CBS brake pads from ISTA as a new brake pads replacement and in this case the counter will increment by 1 even you did not change them. Maybe ISTA will write the settings in all places/ECUs accordingly..


I assume "Code default values" you are reffering to ESYS which is for flashing/coding. i did not use it until now.

indeed, that i wanted to say - at least as you have working brakes...

LE: pads wear algorithm HERE

[DayvG]

in worst case scenario, you can reset CBS brake pads from ISTA as a new brake pads replacement and in this case the counter will increment by 1 even you did not change them. Maybe ISTA will write the settings in all places/ECUs accordingly..

I am thinking that this could be the place to solve the issue but I would like to think there would be a function to write the CBS information to the ECU? I kind of hoped that the VO coding with E-SYS would have synced the CBS information. I will run a measures plan and play with ISTA when I get home. It surely is just a software programming issue.

[danyro]

Nope - esys will not do that. its purpose its purely flashing/coding not initialization etc.
i saw from your previous nightmare topic with ICM error that was fixed via ISTA.

You have also CBS correction in ISTA so you will have to study a bit

keep us posted as i am somehow in the middle of decision to make this retrofit on my F25

[DayvG]

I have all the parts now for the ACC/KAFAS2/HBA/SWW retrofit. New windscreen is on its way from Poland. I have found Allegro is a great place for parts at a great price.

The ACSM fault was purely not completing the start up/initialisation with the extra twisted pair connected from ICM to ACSM, obvious really.

Next step is just clearing the brake fault, there is always something!! Do you think I should attempt resetting the CBS from the KOMBI?

[DayvG]

Solved with a reset back to 50000km. I’m going to get a garage to measure the brake pad thickness then adjust the values so they are accurate. Thanks for your help danyro