Cloning CCM / convenience module?

[pangy101]

Hi guys, I've a few electrical issues with my Passat B7 that I've diagnosed are stemming from a dodgy central convenience unit / comfort module. Not wanting to pay the VW mothership £600 for the pleasure of a new PCB I thought I'd give it a crack at cloning my original CCM and pasting it into a second-hand unit.

Obviously I know a 2nd hand unit could also be dodgy but thought it'd be worth a try for the sake of £30. I've hooked up a USB EEPROM reader to the 95320 EEPROM chip on the CCM and read what I think is a successful read of the chip. I've programmed the second-hand unit's EEPROM with this data... are there are more steps to take in terms of when I hook it up to the car? Will the CAN gateway just see it as the identical unit that I pulled out, or are there other steps to take?

If I manage to get it integrated then I'll change the long coding in OBD11, but wondered if it was a case of just dumping the old unit's EEPROM into the new unit's EEPROM and then plug-and-play?

Cheers!


Also I should add the unit is 3AA959433 - do the software and hardware numbers also need to match (S0634 / H045)?

[Crasher]

From memory that convenience unit is also the immobiliser. New they are a special order Vehicle Intelligent Part from the VIN and cost £478.80 retail inc.

[pangy101]

For anyone else reading I got another used CCM with matching hardware and software versions, dumped the original EEPROM data onto the used CCM and then it worked plug-and-play.

Only problem is that it didn't fix any of my issues! Do you have any ideas Crasher, I'm wondering whether to try changing the Central Electrics unit next - what are your thoughts?

Current problems (all started at roughly the same time):
... Rear boot pops open when you central-unlock the car.
... Rear boot switch on boot doesn't do anything, however OBD shows that the switch is correctly being operated. - checked wiring between boot lid and body - all fine.
... Fuel tank door lock doesn't work (no 12v to lock)
... No indication on instrument display that boot is open when it is and luggage compartment light doesn't work (bulb is fine and 12v to bulb)
... Starter relay circuit error (although checked complete circuit from relays in dash, through both starter relays to ECU - continuity and voltage through all)

No faults shown on an OBD11 scan either (apart from the 'starter relay circuit' fault)... it's driving me crazy!!

If anyone has any ideas please let me know as I'm tearing my hair out with this

[pangy101]

For the benefit of anyone else reading, I got a used central electrics unit, and on my 2013 Passat B7 it was a simple case of swapping the original CECM with the used one and then long-coding it. Unfortunately this hasn't fixed my electrical issues either though, but at least I know it's not the CCM or CECM!

[MP17]

For anyone else reading I got another used CCM with matching hardware and software versions, dumped the original EEPROM data onto the used CCM and then it worked plug-and-play.

Only problem is that it didn't fix any of my issues! Do you have any ideas Crasher, I'm wondering whether to try changing the Central Electrics unit next - what are your thoughts?

Current problems (all started at roughly the same time):
... Rear boot pops open when you central-unlock the car.
... Rear boot switch on boot doesn't do anything, however OBD shows that the switch is correctly being operated. - checked wiring between boot lid and body - all fine.
... Fuel tank door lock doesn't work (no 12v to lock)
... No indication on instrument display that boot is open when it is and luggage compartment light doesn't work (bulb is fine and 12v to bulb)
... Starter relay circuit error (although checked complete circuit from relays in dash, through both starter relays to ECU - continuity and voltage through all)

No faults shown on an OBD11 scan either (apart from the 'starter relay circuit' fault)... it's driving me crazy!!

If anyone has any ideas please let me know as I'm tearing my hair out with this

Hi, what did finally turn out to be the reason for your electrical issues and how did you fix it. Mat

[Crasher]

I have pushed a 2010 3C outside onto the road as the owner cannot afford a new convenience unit since I replaced the column lock which solved the complete electrical shutdown BUT raised the replacement on the inconvenience unit as ducted by VW and my brilliant electronics chap can’t work around so stuffed and the owner has heart problems!

[pangy101]

Hi, what did finally turn out to be the reason for your electrical issues and how did you fix it. Mat

Hi Mat, apart from the starter relay issue, the problem with the other electrics was actually the long coding in the CCM. The garage I had taken the car to swore that they hadn't changed the coding, hence I thought it must have been an error with the CCM itself. After switching it out and having the same issues I tried changing different settings in the long coding and eventually everything functioned as expected. Guess the local garage must have changed something!

[MP17]

Hi pangy101,
got me a used CCM, pluged it in and boot lock worked fine. But I could not get the ignition activated due to immobilizer from 2nd unit not adapted yet, thus I could not read data from 2nd hand comfort unit with VCDS.

The original CCM seems to be mis-coded for the boot lock as it is now working the opposite -> switched to open all the time. I guess that came from a short-circuit inside the broken boot lock. Thats why new boot lock is not doing the trick.
I´m wondering if that can be coded back to standard in CCM with VCDS? But I could not find any entry in VCDS for that. Is there any?

If that is not possible anyway, I guess I need to follow what you have done, swapping the EEPROM to the 2nd hand CCM, right? That EEPROM thing would be a real big deal for me, I m scared messing it up and loosing immobilizer data. Than, I would need to go VW dealer to get a new CCM programmed or is there any other way to save data from EEPROM without soldering. If there is no way around soldering the EEPROM, what devices do I need next to a good soldering iron?

[Crasher]

If you find a way around it, please tell me as I can't find a way and I have a dead car sitting outside the owner can't afford!