No obd2 connection

[Chappo1390]

Hi all I'm having some issues with my 1.9tdi a4 quattro avant. I can't seem to connect to the car with obd2 readers and some times it will show coil light sometimes it dont, when I get coil light it will start if I don't get coil light just turns over. I can connect once I get a Coil light but it's so intermittent. Anyone have any idea what is causing this? 

[Stevey Y]

1 hour ago, Chappo1390 said:

Hi all I'm having some issues with my 1.9tdi a4 quattro avant. I can't seem to connect to the car with obd2 readers and some times it will show coil light sometimes it dont, when I get coil light it will start if I don't get coil light just turns over. I can connect once I get a Coil light but it's so intermittent. Anyone have any idea what is causing this? 

Hi sounds like a glow plug circuit problem but why that would cause a failure of the Can Gateway I don't know, try the simple thing of hosing down the OBD port with electrical cleaner first it could be a filthy pin on the connector.

Steve.

[Chappo1390]

4 hours ago, Stevey Y said:

Hi sounds like a glow plug circuit problem but why that would cause a failure of the Can Gateway I don't know, try the simple thing of hosing down the OBD port with electrical cleaner first it could be a filthy pin on the connector.

Steve.

could this cause it to fail to start to? As I've also been reading could be a communcation error between cluster and ECU 

[Stevey Y]

20 hours ago, Chappo1390 said:

could this cause it to fail to start to? As I've also been reading could be a communcation error between cluster and ECU 

Hi this is a possible but unless you can communicate with it via the OBD this would be difficult to track down in the absence of a fault code, there are others who have posted with a similar problem and it turned out to be dodgy wiring in the boot ECU.

Steve.