VAG-COM Can't find any controllers

[kerrinmay 0]

Maybe a dodgy connection is why my ABS light sometimes comes on (and stays on) when I start the car. Come to think of it, I'm sure it tends to happen more when it's either particuarly cold or damp, so maybe that's affecting a connection somewhere. I'll have to take a look for the ABS controller (is it easy to find?) and check out the connections.

[corradophil 3]

Can anyone explain why you need electronic isolation instead of opto isolation?

[dr_mat 0]

Ross-tech site says electronic isolators are "faster" than opto-isolators.

But opto-isolators are fine for the old, slow ECUs on Corrados.

[kerrinmay 0]

I thought I'd read somewhere that you needed electronic to be able to communicate with the ECU of the 2.0 16v?

[dr_mat 0]

Nope. The VR6 has the most advanced ECU in the Corrado line-up, and it's quite unable to go any quicker than the opto-isolated cables and old-style VAGCOM.

And iirc the main reason VAGCOM 311 is still on ross-tech's website is because it's the only one that works with the old opto-isolator cables.

[Kevin Bacon 5]

It's VAG-COM itself that's slow. The software I use is infinitely faster than VAG-COM using Ross-tech's cable! The ECU can report data as fast as the cable and software can accept it.

[corradophil 3]

So on that basis I should be able to use vag-com 311 and my opto-isolator on my 9A 2.0 16v. I tried ages ago, but the baud rate was set to 0. I've not tried it since because I have been under the impression that an opto-isolator will not work.

 

I will set the baud rate as described and give it a go.

[dr_mat 0]

In other words, you'll follow the instructions! I will not be amazed when it works! ;)

[dr_mat 0]

It's VAG-COM itself that's slow. The software I use is infinitely faster than VAG-COM using Ross-tech's cable! The ECU can report data as fast as the cable and software can accept it.

 

There's always something better. I think VAG-COM does pretty well for a non-professional reverse engineered toolkit ($99 for god's sake). I've not tried the latest VAGCOM with the latest cables either, so I have no idea what it's capable of.

I note you have an OBD2 ECU though..

[corradophil 3]

Had a quick go tonight with Baud rate set to 4800, I get the the too many communications errors message for the ABS. It cannot find the ecu controller. the equipment I have works fine, I used it loads to sort out my Leon which was OBDII.

 

I'm using vagcom 311-2, is this best or is there a better version to use?

[kerrinmay 0]

Glad to see you getting the same comms errors as me with your ABS :wink:

 

Let me know if you discover how to sort it!

[corradophil 3]

Will do, its giving me hope that I can use my opto-isolator which I previously thought was not possible. I think it is more down to software set up now.

 

I was speeking with RW1 last year about this via PM, he is very knowledgable on this. Here is some of what he said.

 

"I have difficulty in recommeding the interface with a 9A engine ECU. The EBAY ones I have reservations with as their build is unknown and the early OBD1 ECU's can be difficult with just one interface to another. Everything settled down after 1994 cars generally so they are likely to tell you it works not thinking of the various querks on OBD1 1992 - 1994 VWs.

 

If you talk to and explain it's the 9A 16v 1992 - 1994 problem with VAG-COM, they will be better able to sort you out :-

 

http://www.skpang.co.uk/

 

or

 

http://www.onboarddiagnostics.co.uk/

 

I would really get someone to plug into the car and then buy that interface as the 9A engine ECU is really picky on what connects to it. I use a Twin-Com from Ross-Tech but they've stop distributing them now. Could always be cheeky with them and ask to but a secondhand one off them.

 

Don't know if your copy of VAG-COM is registered. Going to v409.0 means re-registering the software as Uwe Ross upted the anti on security of his product.

 

Defo you need VAG-COM v409.0 or above for the 9A. Until I got the electronic interface from Ross-Tech and then upgraded to v409.0. Only the ABS would talk on the 9A Corrado."

 

Going by that v409 sounds better, but you got nowhere with that!

[kerrinmay 0]

Yes, it's a shame I couldn't get 409 to work, however it's strange that I can talk ok to the ECU, but just not the ABS. Thought it would be the other way around that I'd have problems. Maybe it's as dr_mat said, that there is a dodgy connection on my ABS controller that's causing this problem with VAG-COM and could also be causing my intermittant fault with the ABS system. I think my best bet will be to actually check the connections and just make sure. I did have a new brake pedal travel sensor fitted about 1 1/2 years ago which got rid of the main ABS fault I had (light used to come on intermittently whilst driving), and then some months after that I started getting this intermittent problem with the light just coming on and staying on sometimes when I start the car.

[kerrinmay 0]

I know it's off topic, but which green is your C Phil?

[corradophil 3]

My ABS works fine, the light always goes out and never comes on to show a fault. The last time it came on was when it was on the rolling road where the rear wheels were not moving!

 

To be honest I am far more interested in the ECU fault codes. I've downloaded and installed v409, but doubt I'll get a chance to look at it untill tomorrow night.

 

kerrinmay, Mine is green pearl effect.

[kerrinmay 0]

kerrinmay, Mine is green pearl effect.

 

Some colour as mine then :)

[corradophil 3]

Yep, maybe its something to do with the colour-why we cannot get vagcom working.

 

kevHaywire, What software do you use?

[corradophil 3]

I've tried vagcom 409 and got nowhere with it which when you read their website is what they say. So 311 is the one to use.

 

kerrinmay, Could you post up the settings you use on yours on the screen where you set up the baud rate. I'm interested to see if your settings are different, and whether that is why you can download codes from the ECU and mine is not responding.

[kerrinmay 0]

Here's a screen shot of the settings that I've got set

[kerrinmay 0]

Please note that I am using an interface with an electrical isolator rather than optical.

[corradophil 3]

Cool, thanks. I'll make sure mine is set the same and have another go later.

 

Maybe the issue is the isolator, although if electrical isolators are newer I'd have thought it would not be so much of a problem, mine being an old car.

 

I'm not too bothered about the ABS faults, but really want to access the ECU codes.

[ismith 0]

I borrowed a 3rd party USB adaptor and can access the ECU on my 93 VR6, but not the ABS. Got the ABS light flashing too and "Too many communications errors". VAGCOM 409 or 311 both unhappy. Feedback is that the adaptor is just not good enough on its timing to please the ABS. Bummer.

 

Rear caliper is seized. Would that turn on the ABS light?

[corradophil 3]

Just been experimenting again with mine.

 

Still cannot find ECU controller, but tries with the ABS and comes up with too many communication errors.

 

I have three ideas left.

 

1. I'm using an adapter from serial to usb, but it works fine on OBDII.

2. My adapter is opto-isolated, maybe it need electronic isolation.

3. A fault with the cars wiring or ECU, VW downloaded the codes a couple of years ago with no problems.

[kerrinmay 0]

I borrowed a 3rd party USB adaptor and can access the ECU on my 93 VR6, but not the ABS. Got the ABS light flashing too and "Too many communications errors". VAGCOM 409 or 311 both unhappy. Feedback is that the adaptor is just not good enough on its timing to please the ABS. Bummer.

 

Rear caliper is seized. Would that turn on the ABS light?

 

That's interesting (and frustrating) about the 3rd party adaptor. I really don't want to have to spend out for a real Ross-Tech one, well actually I really can't afford to! Think I'll still check my wiring though.

[ismith 0]

I think you'll stand more of a chance with a serial port adaptor. These USB ones are less flexible with their timing.