wont connect but correct com port

[Kartmanz]

Hi,
Ive got a mk3 Ibiza TDI sport, I have been trying to connect with Vag-com but It wont connect, I keep getting "no response from controller" error message. Ive tried a few different versions, 4 different cables (one of which ross tech serial cable), and 3 different laptops!!!
Ive set the comm ports as per other threads on SCN, tried different comm ports and bauds, and tried the cable on my brothers A3 tdi and it works!!! , what can be wrong????
Anyone got any ideas??? The car doing my head in now, Ive been tring for about a week, trauling through the threads and what feels like ALL of the internet!!
Please help!!

 

[m0rk]

Sounds like you have iffy wiring. check that the plug is fully engaged with the socket

 

[Kartmanz]

Thanks for the quick reply mate! That was my thinking as well, but I kinda hoped it wasnt and I hadnt done something I was supposed to!! surely the car wouldnt run correctly or show up an error if the wiring was dodgy?
So the only thing to do would be to check each wire individually from the ecu to the OBD plug!!!
Dont suppose anyone has a wiring diag for the OBD plug???

Edit: I have pushed the plug in all the way and the light comes on but could be one dodgy wire.

 

[m0rk]

Light on just means the power I think.

Can you connect to the ABS ECU? or none?

 

[Kartmanz]

Im pretty sure I tried the ABS and it said the same, I tried the instrument cluster(but guess that goes through the main ECU), but I will try the ABS to find out for definate tomorrow.
Thanks for your help mork, If not the ABS dya rekon its wiring by the OBD plug, and if I can connect to ABS the wiring near the ECU??
I did find the ECU had no protective cover so I made one and cleaned the plugs up the other day cos I thought I may have been that but still no joy.

 

[Kartmanz]

Right, Ive checked the car today and tried connecting to the ABS and it says Unable to connect to controller, Ive also tried disconnecting the battery an leaving 10 mins and reconnecting and still no joy?!
Ive checked behind the OBD connector and it only has 2 wires going to it? is this right?? Im sure it would require more wires than that maybe 3 or 4??? I also checked fuses (just in case), Im going to take the OBD port out and check between the port and ECU connector to make sure I have no breaks in the wires! Beyond that Ive no idea!!!!???!?

 

[m0rk]

Pretty sure you have a minimum of four wires for OBDII

+V
0V
Tx
Rx

I'll check on that though

Some cars just won't connect though, I had this problem with a neighbours Mk4 golf (it was ~1998 though)

 

[Kartmanz]

So, Ive checked as much wiring as I can, Theres no cut or disconnected wires, and the ECU connectors seem clean and waterproof.
The OBD connector definatly has 3 wires going to it!
Mork, do you rekon this maybe one I cant connect to? Would a new Ross-tech cable work? If it would then wouldnt mind shelling out as for one as long as its 100% but obviously I cant check it till I buy one!! catch 22 mefinks!