This starter relay J53 is an actuator of the Ecomatic (in contrast to sensors).
Installation location: extra relay bearing under the switchboard
1H0 911 251 VW number
It has the job to amplify the control signal of the control Digiswing.
At the Ecomatic the starter motor is not activated directly by the ignition starter lock.
A signal gives only the Digiswing to the starter relay for the starter motor.
If - self-diagnosis is not completed ,
- conditions for starting on process is not fulfilled (like Gear in the starting prozess engaged, doors openly, no vacuum....)
- or engine turns, no control signal comes of the control box.
You con control the activation by VAGCOM measuring value block display group 4.
The relay is stressed very much by the many start processes and wear out.
A nice side effect of the dismantling and assembly of the relay is the cleaning of the contacts.
Hajo