System Description

WARNING: This page is about a different car, the 2008 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.

Power is supplied at all times:

through 40A fusible link (letter m , located in the fuse and fusible link box)
to ignition switch terminal B.

With the ignition switch in the START position, power is supplied:

from ignition switch terminal ST

to IPDM E/R terminal 4.

With the ignition switch in the ON or START position and the selector lever in the P or N position, power is supplied:

from terminal 24 of the transmission control module (TCM)
to IPDM E/R terminal 53.

Provided that the IPDM E/R receives a starter relay on signal from the BCM over the CAN lines, the IPDM E/R is energized and power is supplied:

from terminal 3 of the IPDM E/R
to terminal S of the starter motor windings.

The starter motor plunger closes and provides a closed circuit between the battery and the starter motor. The starter motor is grounded to the cylinder block. With power and ground supplied, the starter motor operates. In the event that the CAN communication line fails, the IPDM E/R will continue to receive a starter relay on signal from the BCM as long as the ignition switch remains in the START or ON positions.