Civic Sedan L4-1493cc 1.5L SOHC (D15B2) TBI (1989)
Alternator FR Signal: Description and Operation
A/T Shift Position Signal
This signal is sent to the PGM-FI ECU when the transmission is in Neutral, Park, or D4. The signal purpose is to allow the ECU to adjust the
idle speed and mixture to compensate for changing idle conditions, and in the D4 position to enable the lock-up control.