My vehicle is a 2001 Octavia Elegance Estate, 130 tdi, a couple of years ago the airbag warning light came on, at the time I had possibly disturbed the wiring whilst storing something under the seat so was not too concerned especially as here in France the MOT (contrôle technique) is every 2 years so i just let it go.

My vehicle is now long overdue for its test which it will fail if the light is on, I waited since january for the good weather before getting around to this, I dont have a test lead or the software so i took it to a pals garage, its a bit of a qwik-fit type of place, the guys dont really know what they are doing and are not at all communicative.

They connected up a Bosch tester which brought up 2 fault codes which they were unable to erase, I had to try to memorise them as the guy seemed to think they were a state secret but I am quite used to that sort of customer relations in France!

The first was FFFF control box malfunction (boitier de contrôle malfunction) which my pal said would be the airbag control module, the second I cant recall the code but was I think a momentary low voltage signal.

Is it likely that the module will need replacing or could it be perhaps just not communicating for some reason, would connecting it up to VAGCOM in the hands of someone competent be advisable, can the light be reset in that way?

Basically I am looking for any advice, experience or suggestions, the car is not worth a great deal but has many more miles left in her, it would break my heart to scrap her just because of a warning light and "computer says no"

Fortunately I return frequently to the UK so my hands arent as tied as they would otherwise be.

I will be very gratefull for any replies.

Thank you.

Ive got a module if you want it ???

First check the power to the airbag module. If that is OK, then the module is faulty and needs replacing.

the second I cant recall the code but was I think a momentary low voltage signal.

Wasn't "18010/P1602/005634 - Power Supply B+ Terminal 30: Voltage too Low" was it?

That just means you've had the battery disconnected at some point.

The descriptions on the Bosch are about as helpfull as a French mechanic! I remember that it was low voltage (tension basse) and I think momentary but I only got a fleeting glimpse before it was snatched away, I was more concerned with remembering the control box code FFFF.

The battery has been low but never fully discharged in the 7 years I have owned it, I dont have the radio code (another subject) so kept 12v applied when I changed the suspect battery.

I have located the control box but access looks to be a pig to check the supply, I assume that I have to disconnect the battery before removing/replacing the connector to avoid possibly triggering the airbags, is this so? The radio code problem then comes into play

I was actually surprised to see only 2 fault codes and expected loads more, the vanes stick on the turbocharger very frequently, pretty much every journey from a cold start in winter, I feel/hear an overboost belch and then there is practically no boost until I flick the ignition on and off, I expected the memory to be full of these events, I am not sure that the Bosch fault code reader/reset tool is any substitute for the VAG kit

Is failure of these modules a known fault? I ask because they are usually one of the most well built and well protetcted bits of kit on any vehicle, I am fairly sure that the light first came on when the wiring under the seat got pushed by my stowage, when I checked before getting the fault codes read one of the cables going into the connector leading to the drivers seat airbag was under loads of tension, I released the connector and re-routed it, it appears to make contact but may well not have in the past or have been intermittent.

Would the VAG software not show that up as a missing resistance in the circuit, not failure of the module? I am just sceptical of what was displayed and certainly what was not displayed on the Bosch unit, if it were something descriptive and definitive like 18010/P1602/005634 - Power Supply B+ Terminal 30: Voltage too Low" speaking of the module failure I would accept it as gospel.

Edited 9 May, 201214 yr by J.R.

...I was more concerned with remembering the control box code FFFF...

Many Bosch tools display the code in Hex

FFFF (hex) = 65535 (decimal)

see http://wiki.ross-tec...index.php/65535

That is great info!

Possible Causes

• Wiring from/to Control Module faulty
  
  • Voltage Supply and/or Ground Supply faulty
    

  [*]Control Module faulty

  • Control Module Housing leaky
    

Possible Solutions

• Check/Clean Wiring from/to Control Module
  
  • Check Voltage Supply and Ground Supply including the Main Supply/Connections at the Battery
    

  [*]Replace Control Module

Special Notes

• This fault is NOT to be ignored when found in a major and/or critical system (Airbag, ABS etc.). If you try to clear this fault, VCDS may tell you that there is an unexpected result or that the controller refused the command. This is normal since this specific fault can generally not be cleared.
  

So it could just be that there was a fault and that the Bosch tool cannot reset the fault code, would the VAGCOM or whatever it is be able to do so? Would it indicate a problem downstream of the module, say the connector is still not making contact or just that the module is not working?

thanks for all your responses so far

The 65535 is a special code when referencing the airbag control unit. This code is generated when the dash insert/CCU cannot read the status of the control unit. The fault really means that it is not possible to check for faults.

The power comes direct from the ignition switch - black wire at the airbag connector.

The earth is the brown wire at the airbag connector.

On at least one wiring variant I've seen, you can create this error if you unplug both passenger and driver side airbags (3-pin connectors under the seats).

You say your car is a 2001 130hp tdi. What is 3 character engine code? ASV? AHF?

I made a mistake, its the 81kw ASV engine, mechanical injectors.

From what I have learned from you kind people it looks like everything could now be OK but that I need to connect it up to VAG;COM to remove the fault code and reset the airbag light, is there anyone in the south east of england who help me out with this? i live in the Gatwick area when I return.

There's a section on these forums for VCDS & Diagnostics if you ask in there or I think theres a thread with a list of VCDS owners and where they are. It doesn't sound to me like VCDS will be able to clear the fault though from what it says on the Ross-Tech website above. You might have to either replace the module or as rwbaldwin is suggesting check there is power to it.

Sorry to be naive but what is VCDS? had I known I may have posted in that section.

I tried to post in the technical questions section but there was a message at the top saying that I cannot post in this section, lord only knows why!

Have I posted my question in the wrong section of the forum? If so I am all the more pleased with the responses. If this should be in another section would it be possible for one of the moderators to move it for me?

VCDS stands for VAG-Com Diagnostics System, it's made by Ross-Tech.

Its just your best bet if you want someone with VCDS in the South East to look at your car will be to post in the VCDS section or one of the Local sections (South East) rather than here in the Octavia I section although this section is pretty handy for problems with the Mk1 Octavia anyway. Probably best to leave this thread here and return to it later if and when you've found someone to VAG-Com the car.

OK will do, I have just read the first few pages of the VCDS section, very enlightening, thank you to all who have responded to date, my knowledge has already increased exponentionally, that plus I now have some confidence that I will be able to take some control of the problem after all.