I recently picked up a used A4 and I believe the previous owner disconnected the check engine light. Does anyone know how I would go about reconnecting it? I do not even know where it is located.

The reason this is significant is that I happen to live in California and as a result I have to have the vehicle inspected and smog tested. One part of the smog test is that they check to ensure that your check engine light comes on at start up (which mine does not).

I also think that this check engine light being disconnected is also causing other problems as I have two error codes coming up that I can not figure out. If anyone has any input on the following codes and whether not having the check engine light connected makes sense as to why they are coming up I would greatly appreciate any advice?

Fault Codes:

P0705: Trans Range Sensor Malfunction (PRNDL Input)
P0422: Main Cat Efficiency Below Threshold (Bank 1)