Intermittent Operation

WARNING: This page is about a different car, the 2005 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.

The rear wiper motor operates the wiper arm at low speed approximately every 7 seconds.

When the wiper switch is in the rear wiper INT position, the BCM detects a rear wiper INT request through the combination switch (wiper switch) reading function.

The BCM controls rear wiper motor operation by switching direction of current flow between the two rear wiper motor output circuits.

Power is supplied to output circuit 1 for forward operation (counterclockwise sweep),

through BCM terminal 55
to rear wiper motor terminal 4.

Ground is supplied

to rear wiper motor terminal 6
through BCM terminal 54
through BCM terminal 67
through grounds M57, M61 and M79.

With output circuit 1 power and ground supplied, the rear wiper motor operates in a counterclockwise sweep direction until auto stop switch 1 closes (full sweep position). Auto stop switch 1 supplies ground

to BCM terminal 44
through rear wiper motor terminal 2
through rear wiper motor terminal 5
through grounds B117 and B132.

When the BCM receives this ground signal it turns off output circuit 1 and turns on output circuit 2.

Power is supplied to output circuit 2 for reverse operation (clockwise sweep),

through BCM terminal 54
to rear wiper motor terminal 6.

Ground is supplied

to rear wiper motor terminal 4
through BCM terminal 55
through BCM terminal 67
through grounds M57, M61 and M79.

With output circuit 2 power and ground supplied the rear wiper motor operates in a clockwise sweep direction until auto stop switch 2 closes (full sweep position). Auto stop switch 2 supplies ground

to BCM terminal 26
through rear wiper motor terminal 1
through rear wiper motor terminal 3
through grounds B117 and B132.

When the BCM receives this ground signal it turns off output circuit 2 and starts the timing function of 7 seconds. After approximately 7 seconds the BCM turns on output circuit 1. This process repeats until the rear wiper switch or ignition switch is turned off.