Nissan Quest E52. Manual - part 927

PCS

SYSTEM

PCS-5

< SYSTEM DESCRIPTION >

[IPDM E/R]

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SYSTEM

RELAY CONTROL SYSTEM

RELAY CONTROL SYSTEM : System Description

INFOID:0000000009652846

SYSTEM DIAGRAM

DESCRIPTION

IPDM E/R activates the internal control circuit to perform the relay ON-OFF control according to the input sig-
nals from various sensors and the request signals received from control units via CAN communication.

CAUTION:

To prevent damage to the parts, IPDM E/R integrated relays cannot be removed.

JMMIA0834GB

PCS-6

< SYSTEM DESCRIPTION >

[IPDM E/R]

SYSTEM

*: BCM controls the starter relay.

RELAY CONTROL SYSTEM : Fail-safe

INFOID:0000000009978055

CAN COMMUNICATION CONTROL

When CAN communication with ECM and BCM is impossible, IPDM E/R performs fail-safe control. After CAN
communication recovers normally, it also returns to normal control.

If No CAN Communication Is Available With ECM

Control relay

Input/output

Transmit unit

Control part

Reference page

Headlamp low relay

Low beam request signal

BCM (CAN)

Headlamp (LO)

•

EXL-12

 (Xenon 

type)

•

EXL-124

 (Halo-

gen type)

Headlamp high relay

High beam request signal

BCM (CAN)

Headlamp (HI)

Front fog lamp relay

Front fog light request signal

BCM (CAN)

Front fog lamp

•

EXL-26

 (Xenon 

type)

•

EXL-138

 (Halo-

gen type)

Tail lamp relay

Position light request signal

BCM (CAN)

• Parking lamp
• license plate lamp
• Tail lamp
• Side marker lamp

•

EXL-23

 (Xenon 

type)

•

EXL-135

 (Halo-

gen type)

Illumination

INL-15

• Front wiper relay
• Front wiper high relay

Front wiper request signal

BCM (CAN)

Front wiper motor

WW-8

Front wiper stop position sig-
nal

Front wiper motor

Horn relay

• Theft  warning  horn request 

signal

• Horn reminder signal

BCM (CAN)

• Horn (high)
• Horn (low)

SEC-21

• Starter relay*
• Starter control relay

Starter control relay signal

BCM (CAN)

Starter motor

SEC-6

Starter relay control signal

TCM

Starter motor relay cut off sig-
nal

ECM (CAN)

EC-55

A/C relay

A/C compressor request sig-
nal

ECM (CAN)

A/C compressor
(magnet clutch)

•

HAC-19

 (Auto-

matic air condi-
tioning)

•

HAC-163

 (Manu-

al air condition-
ing)

• Cooling fan relay-1
• Cooling fan relay-2
• Cooling fan relay-3

Cooling fan speed request sig-
nal

ECM (CAN)

• Cooling fan motor-1
• Cooling fan motor-2

EC-45

Ignition relay

Ignition switch ON signal

BCM (CAN)

Each control unit, sensor, 
actuator and relay (igni-
tion power supply)

PCS-31

Vehicle speed signal

Combination meter 
(CAN)

Push-button ignition switch 
signal

Push-button ignition 
switch

Daytime running light relay

Daytime running light request 
signal

BCM (CAN)

Headlamp (HI)

•

EXL-20

 (Xenon 

type)

•

EXL-132

 (Halo-

gen type)

PCS

SYSTEM

PCS-7

< SYSTEM DESCRIPTION >

[IPDM E/R]

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If No CAN Communication Is Available With BCM

IGNITION RELAY MALFUNCTION DETECTION FUNCTION

• IPDM E/R monitors the voltage at the contact circuit and excitation coil circuit of the ignition relay inside it. 
• IPDM E/R judges the ignition relay error if the voltage differs between the contact circuit and the excitation

coil circuit.

• If the ignition relay cannot turn OFF due to contact seizure, it activates the tail lamp relay and daytime run-

ning light relay for 10 minutes to alert the user to the ignition relay malfunction when the ignition switch is
turned OFF.

FRONT WIPER PROTECTION FUNCTION

IPDM E/R detects front wiper stop position by a front wiper stop position signal.
When a front wiper stop position signal is in the conditions listed below, IPDM E/R stops power supply to wiper
after repeating a front wiper 10 seconds activation and 20 seconds stop five times.

Control part

Fail-safe operation

Cooling fan

• Turns ON the cooling fan relay-2 and the cooling fan relay-3 when the ignition switch is 

turned ON (Cooling fan operates at HI)

• Turns OFF the cooling fan relay-1, the cooling fan relay-2 and the cooling fan relay-3 

when the ignition switch is turned OFF (Cooling fan does not operate)

A/C compressor

A/C relay OFF

Alternator

Outputs the power generation command signal (PWM signal) 0%

Control part

Fail-safe operation

Headlamp

• Turns ON the headlamp low relay when the ignition switch is turned ON
• Turns OFF the headlamp low relay when the ignition switch is turned OFF
• Headlamp high relay OFF

• Parking  lamp
• License plate lamp
• Illumination
• Tail lamp
• Side marker lamp

• Turns ON the tail lamp relay when the ignition switch is turned ON
• Turns OFF the tail lamp relay when the ignition switch is turned OFF

Front wiper motor

• The status just before activation of fail-safe control is maintained until the ignition switch 

is turned OFF while the front wiper is operating at LO or HI speed.

• The wiper is operated at LO speed until the ignition switch is turned OFF if the fail-safe 

control is activated while the front wiper is set in the AUTO mode and the front wiper motor 
is operating.

• Returns automatically wiper to stop position when ignition switch is turned ON if fail-safe 

control is activated while front wiper motor is operated and wiper stop in the other than 
stop position.

Front fog lamp

Front fog lamp relay OFF

Horn

Horn relay OFF

Ignition relay

The status just before activation of fail-safe is maintained.

Starter motor

Starter control relay OFF

Voltage judgment

IPDM E/R judgment

Operation

Ignition relay con-

tact side

Ignition relay exci-

tation coil side

ON

ON

Ignition relay ON normal

—

OFF

OFF

Ignition relay OFF normal

—

ON

OFF

Ignition relay ON stuck

• Detects DTC “B2098: IGN RELAY ON”
• Turns ON the tail lamp relay for 10 minutes

OFF

ON

Ignition relay OFF stuck

Detects DTC “B2099: IGN RELAY OFF”

PCS-8

< SYSTEM DESCRIPTION >

[IPDM E/R]

SYSTEM

NOTE:
This operation status can be confirmed on the IPDM E/R “Data Monitor” that displays “BLOCK” for the item
“WIP PROT” while the wiper is stopped.

STARTER MOTOR PROTECTION FUNCTION

IPDM E/R turns OFF the starter control relay to protect the starter motor when the starter control relay remains
active for 90 seconds.

POWER CONTROL SYSTEM

POWER CONTROL SYSTEM : System Description

INFOID:0000000009652848

SYSTEM DIAGRAM

DESCRIPTION

Alternator Control

IPDM E/R outputs power generation command signal (PWM signal) to the alternator according to the status of
the power generation command value signal received from ECM via CAN communication. Refer to 

CHG-8,

"CHARGING SYSTEM : System Description"

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SIGNAL BUFFER SYSTEM

SIGNAL BUFFER SYSTEM : System Description

INFOID:0000000009652849

SYSTEM DIAGRAM

DESCRIPTION

• IPDM E/R reads the status of the oil pressure switch and transmits the oil pressure switch signal to BCM via

CAN communication. Refer to 

MWI-16, "OIL PRESSURE WARNING LAMP : System Description"

.

Ignition switch

Front wiper switch

Front wiper stop position signal

ON

OFF

The front wiper stop position signal (stop position) cannot be input for 10 seconds.

ON

The front wiper stop position signal does not change for 10 seconds.

JMMIA0810GB

JMMIA0835GB