Circuit Operation

Battery positive voltage is applied to the Park/Neutral position switch (terminal 8) when the ignition switch is turned "ON."
Battery positive voltage is applied to the PCM (terminal 101) when the selector lever is in the "P" range. The PCM judges that the selector lever is in the "P" range when the battery positive voltage is applied.
Battery positive voltage is applied to the PCM terminal 108 (121, 102, 109, 122 or 110) when the selector lever is in the "R" range ("N," "D," "3," "2" or "L" range). The PCM judges that the selector lever is in the "R" range ("N," "D." "3," "2" or "L" range) when the battery positive voltage is applied.