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Diagnostic Signal

OPERATION
The Diagnostic Signal is connected to pin C 12 of the MPI control module, the signal is directional OUT only (PIN C 12 - OUTPUT ONLY).

PURPOSE
The diagnostic signal is used for communication between the MPI control module and special tool V.A.G. 1551. The signal is also used for Blink Code Output.

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".