Can you even use VCDS with a Felly? I'm pretty much certain that no Felly ever had azure dentition as standard.

This is all you'll ever need for your car: Motordiag VAG 5053 (VW, Škoda, Audi, Seat)

Supported cars

Škoda: Favorit (with injection), Felicia (6X) 1996 - 2001, Felicia Pick Up (67), Fabia (6Y) 2000 ->, Fabia II 2007 ->, Octavia I (1U) 1997 - 2005, Octavia II (1Z) 2005 ->, Pick Up (67) 1996 - 2001, Superb (3U) 2002 ->, Roomster 2006 ->,

Volkswagen: Caddy (9K) 1996 - 2003, Caddy (2K) 2004 ->, Corrado (50) 1989 -> 1995, Eos (1F) 2006 ->, Fox (5Z) 2005 ->, Gol/Parati/Saveiro (5X) 2000 ->, Golf II / Jetta II (19E) 1983 - 1992, Golf III / Jetta III / Vento / Cabrio (1H) 1992 - 1998, Golf IV Cabrio (1E) 1999 - 2002, Golf IV / Bora / Jetta IV (1J) 1998 - 2005, Golf V / Golf Plus / Jetta (1K/5M) 2004 ->, LT (2D) 1996 ->, Lupo (6E/6X) 1999 ->, New Beetle / Cabrio (1C/1Y/9C) 1999 ->, Passat (31/3A) 1988 - 1994, Passat (3B) 1997 ->, Passat (3C) 2005 ->, Phaeton (3D) 2002 ->, Polo (6N/6N2) 1994 - 2002, Polo (9N) 2002 ->, Sharan (7M) 1995 ->, Touareg (7L) 2003 ->, Touran (1T) 2003 ->, Transporter (70) 1991 - 1996, Transporter (7D) 1997 - 2003, Transporter (7H/7J) 2003 ->,

AUDI: A2 (8Z) 2000 ->, A3/S3 (8L) 1997 - 2003, A3 (8P) 2004 ->, Coupe (8B) 1989 - 1994, 80 (8C) 1992 - 1995, A4/S4 (8D) 1995 - 2001, A4/S4/Cabriolet (8E/8H) 2001 ->, 100/A6/S6 (4A) 1991 - 1997, A6/RS6/S6/allroad (4B) 1997 - 2005, A6 (4F) 2005 ->, Q7 (4L) 2006 ->, A8/S8 (4D) 1994 - 2002, A8 (4E) 2003 ->, TT (8N) 1999 ->, TT (8J) 2006 ->, V8 (44/4C) 1989 - 1994,

SEAT: Alhambra (7M) 1996 ->, Altea (5P) 2004 ->, Arosa (6B/6H) 1997 - 2004, Ibiza / Cordoba (6K) 1993 - 2002, Ibiza / Cordoba (6L) 2002 ->, Inca (9K) 1996 - 2003, Leon / Toledo (1M) 2000 ->, Leon (1P) 2006 ->, Toledo (1L) 1992 - 1999, Toledo (5P) 2005 ->

Edited 9 April, 201313 yr by adurer

Can you even use VCDS with a Felly? I'm pretty much certain that no Felly ever had azure dentition as standard.

Yes, all of them work with it. Seriously, Ken, you seem to just comment on threads when you have no clue about the details - suggesting an MPi Felicia needed new spark plug leads, etc. If you don't know, then keep schtum.

I always thought that the white box on the alternator was there purely for interference suppression for the radio. I've only ever seen one Felicia without an immobiliser, that was a 1994 on a M plate, it's actually law here that all cars made after a certain date (I think 1995) should have an immobiliser fitted.

There's not too many control units on a Felicia, but VCDS will access them, engine 01, airbags 15, immobiliser 25 and diesel electronics 42 is about all they've got.

i'm with fordfan on this one,although it may well be a capacitor in parallel with a spike suppressor . ( Spike suppressor prevents excessive voltage spikes from damaging capacitor) . A very basic digital voltmeter won't cost the earth and is sufficient for the beginner, and is better than a analogue style meter for the beginner as you don't have to worry about voltage polarity . If you connect it right way round it'll show something like 12.8v dc . Wrong way will read -12.8 . If you fond a DVM with autorange and hold facility in your price range ,so much the better . Autorange will set range automaticall ( great for checking voltage drop on solenoids etc ) with hold allowing you to keep reading till you discard it .

( Spike suppressor prevents excessive voltage spikes from damaging capacitor)

Wrong. A spike (or surge) suppressor (usually a varistor or other semiconductor) has the role of protecting a CIRCUIT from excessive transient voltage, in our case the car DC power supply circuit, not the capacitor itself (which has a filtration role btw).

Edited 9 April, 201313 yr by adurer

I'd suggest you think again. The capacitor has a finite working voltage. Exceeed that voltage and capacitor goes bang .( believe me ,I've seen many caps go bang because of this ). A spike supressor of any type strikes at a set voltage to limit the voltage across cap and prevent bang. The circiut you talk of has the cap connected across it AND THE DC CAR POWER SUPPLY. The spikes are caused by L di/dt processes. I could go further into the maths, but that's not the point.

I know a capacitor has a max rated voltage, but to say a semiconductor is put in parallel to protect a capacitor... that's plain stupid.

The way things work is this: the voltage regulator is keeping a quasi stable voltage across car's DC main circuit. In addition to that, a varistor (variable resistor) is put across regulated DC main circuit to protect it against excessive transient voltages caused by back EMF generated in alternator. Further more, a capacitor is put in parallel to varistor to integrate (smoothen) any spike short enough that may pass the varistor. Trust me on that and let it go. We all make mistakes.

@ChrissyM

Yeah, under normal circumstances, the little white box is not really necessary, but you may never know what sensitive electrical device may fry/malfunction (immobilizer included) due to some overvoltage spike. Let's remember that alternators are using brushes to work (I'll tell you why if you want) and they produce a lot of power surges, especially on high electrical load, either commanded (lights, fans, heaters, etc.) or accidental (like a dry battery acting as a quasi short).

Edited 10 April, 201313 yr by adurer

Hi,i have had a dozen names for the white box but i have replaced it anyway but it is still the same. I have tried everything and am almost 100% it is the immobiliser. I didnt know it had one as its so basic and the key doesnt look like it either. I have ordered a reader on the net it should be here tomorrow. Will this tell me the fault and will it reset the fault. Thanks for the immo' info by the way. Can i bypass the immobiliser to test it ? Any advice will be useful.thanks

I have checked on my car. Its a 2.2 microfarad capacitor and a diode connected in parallel (circuit diagram is actually printed on the white box) on my 1.3 MPi. I coulnt find the voltage marked but there was a second stamping on another metal plate nearby saying "14V" which seems odd to me, I have never come across a 14V supply before. I did take a photo of needed.

But if its been replaced then it doesnt really matter what it is :p

Hi,i have had a dozen names for the white box but i have replaced it anyway but it is still the same. I have tried everything and am almost 100% it is the immobiliser. I didnt know it had one as its so basic and the key doesnt look like it either. I have ordered a reader on the net it should be here tomorrow. Will this tell me the fault and will it reset the fault. Thanks for the immo' info by the way. Can i bypass the immobiliser to test it ? Any advice will be useful.thanks

I doubt very much the scanner will do more than letting you know there is an immobilizer problem. Let's not forget how all started: a massive overvoltage that probably fried the immobilizer and/or associated parts. So you're looking at new immobilizer and paired keys. As for bypassing part, nobody knowing how will tell you public for obvious reasons.

Of course the other way you could pop the condenser is by connecting up some jump leads to the car with the wrong polarity, could also pop the ecu.

I'm not going to get into an argument about condensers, but it makes no difference if the condenser is there or not, it has no effect on voltage output of the alternator whatsoever, it is purely a passive filter to route electronic noise to ground.

I doubt very much the scanner will do more than letting you know there is an immobilizer problem. Let's not forget how all started: a massive overvoltage that probably fried the immobilizer and/or associated parts. So you're looking at new immobilizer and paired keys. As for bypassing part, nobody knowing how will tell you public for obvious reasons.

Will the immobiliser and keys have to come off my model or is there others i can check, will i not need the ecu also or the ecu remapping afterwards.

If you get the immo box (shown in adurer's photo), and a keys with matching immo chips in them, the only thing you'll have to do is use VAG-COM (VCDS) to get the two to work together, I think. Tom knows all about how to do this, and I'm pretty sure it's on here somewhere, it's not difficult, IIRC.

Then, of course you have to get the glass immo chip out of the "new" key and put it into the "old" key as your old key is obviously cut to fit your locks, but that's easy enough, I think.

This is, of course, if the immo box is the problem.

^^ yeah if you have a key and immo box that is already pair together it's easy to match it to the ecu, you just go into immo (25) adaption (10), channel 0, read then save a 0 to this channel and it matches the immo unit to the ecu...

however if the key is NOT matched to the immo unit you will need the immobilizer pin number to login and match the key to the immo unit..

if i'm honest i wouldnt suspect the immo box is at fault in this case, it's more likely to be a simple electrical problem at first

I have tried all of the little knowledge i have but if anyone would like to educate me in how to diagnose the fault correctly it would be very much appreciated !

ok, start again, there's too much diluted info in here, tell me from the top what happened and why, and what you've tried

I have tried all of the little knowledge i have but if anyone would like to educate me in how to diagnose the fault correctly it would be very much appreciated !

You already told us in detail what happened and what you tried and replaced. Trying to repair an immobilizer issue is not a job for beginners.

ok, start again, there's too much diluted info in here, tell me from the top what happened and why, and what you've tried

ok, start again, there's too much diluted info in here, tell me from the top what happened and why, and what you've tried

the battery frazzled due to the alternator and also the little suppresor on The alternator. The fuse for the fuel pump also blew. I changed all these. Somebody said change the ecu which without thinking i stupidly did. I have put the original one back on now. I think this may have confused it and needs resetting.either this or the immo blew. The car will start but not run.it starts and cuts out after a second or two.

The old ECU would not have "forgotten" its programming to the immo box by removing it and putting another one in.

it depends on which version of the firmware it has darren, i suspect it will have an 'engine start blocked' fault code stored in it, plus the immo unit will need the basic settings reset before it will play again... you need a vagcom user to help you i'm afriad, either that or you need to go to the dealer and get the daignostics done before you spend any money on it on random parts...

but first and foremost you need to figure out why the fuse and condensor blew up, it is likely that the voltage regualtor in the alternator has failed and it's churning out too much voltage, you need to sort that first before doing anything

While driving the car cut out with no power,i lifted the hood and the battery was dry and a little white box on the back of the alternator had exploded !

Just to clear things a bit, because something caught my eye, when you said "dry" battery, did you mean that literally? Like seeing through translucent battery case that electrolyte level is low? Or did you mean it had no more power?

I guess the former, because you can't see how much power you have left in your battery right after lifting the hood.

Having said that, it is very probable that for whatever reason voltage regulator got toasted (parts don't have infinite life) which in turn blew the poor little white box, which in turn subjected the battery to a dangerously high charging current. That made the battery electrolyte literally boil and dry fast. With that in mind, I hope you changed the battery too, and not let us think there are other issues involved (like bad immobilizer) when the issue could be a weak, quasi dead, shocked battery...

Edited 12 April, 201313 yr by adurer

Yeh i have got it into a garage on monday for diagnostics to check and sort if that is the problem. The battery went due to the power regulator but i have changed the whole alternator so that should be ok. So you think it all may just need reseting at the garage. I bought a reader/resetter but it is obd2 and apparently the car is obd an older version so it just says connection failure.:-(