Dropping connection

[mephisto]

I have some issues with my Audi S3 8L keeps dropping connection or wont connect.

Problem is i had ABS light on and wanted to reset, error codes were related to the pump and a sensor but halfway through the connection would drop. Same if im attempting to connect to Engine module. Its very intermittent.
Strangely seems ok when i first connect then progressively worse where it disconnects and i can't connect again.

I read that faulty devices can cause interference on the kline? So i unplugged the ABS module complete and still have the same issue trying to connect to the ECU or engine module.

Id appreciate some help here how i may diagnose. I have 3 obd readers VCDS/OBdeleven and a standard OBdreader (Xtool) unit which all work perfect on my other S3.

Thanks!

 

[mephisto]

Oh my no help at all? Be most appreciated!

 

[AlS3BE]

Could be the cable is broken inside.
had an old vcds cable that did that and wire broke around the usb connector. Had to chop it off and solder back together. There’s 5 or 6 wires inside plus the shielding and insulation and all very thin cables.

 

[mephisto]

Could be the cable is broken inside.
had an old vcds cable that did that and wire broke around the usb connector. Had to chop it off and solder back together. There’s 5 or 6 wires inside plus the shielding and insulation and all very thin cables.

THanks for your input here, as above ive tested with 2 difference cable methods and a bluetooth obd connector all 3 show similar issues.
I feel im at the point i need to start testing voltages. I dropped the connector down from the dash and check the appearance of all connections there look good. Wires run up into a big fat loom look ok.

 

[AlS3BE]

Maybe a short to ground somewhere or a dodgy old battery.
not sure where to start to look though. maybe start with wires that move like doors and boot.

 

[mephisto]

OK in the end i think it was my head unit and or a load of wiring i pulled out where someone had fitted an after market Parrot style bluetooth unit.