Nissan Sentra Service Manual: System description

Component parts

Component parts location

1. Ipdm e/r (contains ignition relay-1)
2. Bcm (view with instrument panel removed)
3. Fuse block (j/b) (front)
4. Fuse block (j/b) (back)
5. Blower relay
6. Ignition relay-2
7. Accessory relay-1
8. Push-button ignition switch

Component description

System

Power distribution system

Power distribution system : system diagram

Power distribution system : system description

System description

• PDS (POWER DISTRIBUTION SYSTEM) is the system that BCM controls with the operation of the pushbutton ignition switch and performs the power distribution to each power circuit. This system is used instead of the mechanical power supply changing mechanism with the operation of the conventional key cylinder.
• The push-button ignition switch can be operated when intelligent key is in the following condition.

• Intelligent key is in the detection area of the inside key antenna.
• Intelligent key backside is contacted to push-button ignition switch.

• The push-button ignition switch operation is input to bcm as a signal. Bcm changes the power supply position according to the status and operates the following relays to supply power to each power circuit.

• Ignition relay-1
• Ignition relay-2
• Accessory relay-1
• Accessory relay-2
• Blower relay

Note:

The engine switch operation changes due to the conditions of brake pedal, selector lever and vehicle speed.

• The power supply position can be confirmed with the lighting of the indicators in the push-button ignition switch.

Battery saver system

When all the following conditions are met for 30 minutes, the battery saver system will cut off the power supply to prevent battery discharge.

• The ignition switch is in the ACC or ON position
• All doors are closed
• Selector lever is in the p (park) position

Reset condition of battery saver system

In order to prevent the battery from discharging, the battery saver system will cut off the power supply when all doors are closed, the selector lever is in p (park) position and the ignition switch is left in the acc or on position for 30 minutes. If any of the following conditions are met the battery saver system is released and the steering will change automatically to lock position from off position.

• Opening any door
• Operating door request switch on door handle
• Operating Intelligent Key

Power supply position change table by push-button ignition switch operation

The power supply position changing operation can be performed with the following operations.

Note:

• When an Intelligent Key is within the detection area of inside key antenna and when Intelligent Key backside is contacted to push-button ignition switch, it is equivalent to the operations below.
• When starting the engine, the BCM monitors under the engine start conditions:

• Brake pedal operating condition
• Selector lever position
• Vehicle speed

Vehicle speed: less than 4 km/h (2.5 MPH)

Vehicle speed: 4 km/h (2.5 Mph) or more

Emergency stop operation

• Press and hold the push-button ignition switch for 2 seconds or more.
• Press the push-button ignition switch 3 times or more within 1.5 Seconds.