Diagnostic Signal
OPERATIONThe Diagnostic Signal is connected to pin C 12 of the Engine Control Module, the signal is directional OUT only (PIN C 12 - OUTPUT ONLY).
PURPOSE
The diagnostic signal is used for communication between the Engine Control Module and special tool V.A.G. 1551.
SIGNAL FAILURE
^ When there is a break in the signal wiring (K-wire), the following text appears on the V.A.G. 1551: "control module does not answer".