This signal is sent to the control unit during starter operation.
Measure voltage between 30 (Blue/Red (+)) and 32 (black (-)) contacts with the ignition key in the START position.
If battery voltage is present, then the starter signal is normal.
If there is no voltage, then check the fuse number 10 (7.5 A).
If the fuse is OK, then you should repair the breakage of the Blue / Red wire between fuse No. 10 and terminal 30 of the control unit.
If the fuse is blown, it should be replaced.