control unit NISSAN NAVARA 2005 Repair Workshop Manual

MTC-62
TROUBLE DIAGNOSIS
7.CHECK PBR FEEDBACK SIGNAL
1. Reconnect the front air control connector and mode door motor
connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M98
terminal 21 and ground.
4. Press mode switch through all modes.
OK or NG
OK >> Replace front air control. Refer toMTC-98, "CONTROL
UNIT".
NG >> GO TO 8.
8.CHECK PBR FEEDBACK CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect the mode door motor connector and front air control
harness connector.
3. Check continuity between mode door motor harness connector
M46 terminal 4 and front air control harness connector M98 ter-
minal 21.
OK or NG
OK >> Replace mode door motor. Refer toMTC-110, "MODE
DOOR MOTOR".
NG >> Repair or replace harness as necessary.21 - Ground : Approx. 0 - 5V
WJIA1088E
4 - 21 : Continuity should exist.
WJIA1089E

MTC-64
TROUBLE DIAGNOSIS
SYSTEM DESCRIPTION
Component Parts
Air mix door control system components are:
lFront air control
lAir mix door motors (Front and rear)
lPBR (built-into air mix motors)
System Operation
The front air control receives data from the temperature selected by the driver and rear passenger. The front
air control then applies a voltage to one circuit of the appropriate air mix door motor, while ground is applied to
the other circuit, causing the appropriate air mix door motor to rotate. The direction of rotation is determined by
which circuit has voltage applied to it, and which one has ground applied to it. The front air control monitors the
air mix door positions by measuring the voltage signal on the PBR circuits of each door.
Air Mix Door Control Specification
COMPONENT DESCRIPTION
Air Mix Door Motors
The air mix door motor is attached to the heater & cooling unit. This
motor rotates so that the air mix door is opened or closed to a posi-
tion set by the front air control. Motor rotation is then conveyed
through a shaft and the air mix door position is then fed back to the
front air control by the PBR built into the air mix door motor.
NOTE:
This illustration is for LHD models.
The layout for RHD models is symmetrically opposite.
DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (FRONT)
1.CHECK RESULT FROM FRONT AIR CONTROL SELF-DIAGNOSIS OR PROCEED FROM SYMPTOM
TABLE
Is vehicle equipped with NAVI?.
YESorNO
YES >> GO TO 2.
NO >> GO TO 4.
2.CHECK RESULT FROM FRONT AIR CONTROL SELF-DIAGNOSIS
Self-diagnosis code 22 is present. Refer toMTC-51, "
A/C System Self-diagnosis Function".
YESorNO
YES >> GO TO 3.
NO >> GO TO 4.
WJIA0435E
MJIB0192E

MTC-66
TROUBLE DIAGNOSIS
5.CHECK PBR REFERENCE VOLTAGE CIRCUIT BETWEEN AIR MIX DOOR MOTOR (FRONT) AND
FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect the front air control connector.
3. Check continuity between air mix door motor (Front) harness
connector M99 terminal 1 and front air control harness connec-
tor M98 terminal 23.
OK or NG
OK >> Replace front air control. Refer toMTC-98, "CONTROL
UNIT".
NG >> Repair or replace harness as necessary.
6.CHECK PBR GROUND REFERENCE CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect the front air control connector.
3. Check continuity between air mix door motor (Front) harness
connector M99 terminal 3 and front air control harness connec-
tor M98 terminal 26.
OK or NG
OK >> GO TO 7.
NG >> Repair or replace harness as necessary.1 - 23 : Continuity should exist.
MJIB0096E
3 - 26 : Continuity should exist.
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TROUBLE DIAGNOSIS
MTC-67
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MTC
7.CHECK PBR FEEDBACK SIGNAL
1. Turn ignition switch OFF.
2. Reconnect the front air control connector and air mix door motor
(Front) connector.
3. Check voltage between front air control harness connector M98
terminal 22 and ground.
4. Rotate Front temperature dial through complete range.
OK or NG
OK >> Replace front air control. Refer toMTC-98, "CONTROL
UNIT".
NG >> GO TO 8.
8.CHECK PBR FEEDBACK CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect the air mix door motor (Front) connector and front air
control connector.
3. Check continuity between air mix door motor (Front) harness
connector M99 terminal 2 and front air control harness connec-
tor M98 terminal 22.
OK or NG
OK >> Replace air mix door motor (Front). Refer toM T C - 111 ,
"AIR MIX DOOR MOTOR".
NG >> Repair or replace harness as necessary.22 - Ground : Approx. 0V - 5V
MJIB0098E
2 - 22 Continuity should exist.
MJIB0099E

TROUBLE DIAGNOSIS
MTC-69
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MTC
SYSTEM DESCRIPTION
Component Parts
Intake door control system components are:
lFront air control
lIntake door motor
System Operation
The intake door control determines the intake door position based on the position of the recirculation switch.
When the recirculation switch is depressed the intake door motor rotate closing off the fresh air inlet and recir-
culating the cabin air. If the recirculation switch is depressed again, the intake door motor rotate in the oppo-
site direction, again allowing fresh air into the cabin.
Intake Door Control Specification
COMPONENT DESCRIPTION
Intake door motor
The intake door motor is attached to the intake unit. It rotates so that
air is drawn from inlets set by the front air control. Motor rotation is
conveyed to a lever which activates the intake door.
NOTE:
This illustration is for LHD models.
The layout for RHD models is symmetrically opposite.
DIAGNOSTIC PROCEDURE FOR INTAKE DOOR MOTOR
1.CHECK RESULT FROM FRONT AIR CONTROL SELF-DIAGNOSIS OR PROCEED FROM SYMPTOM
TABLE
Is vehicle equipped with NAVI?.
YES or NO
YES >> GO TO 2.
NO >> GO TO 4.
2.CHECK RESULT FROM FRONT AIR CONTROL SELF-DIAGNOSIS
Self-diagnosis code 82 is present. Refer toMTC-51, "
A/C System Self-diagnosis Function".
YES or NO
YES >> GO TO 3.
NO >> Replace front air control. Refer toMTC-98, "
CONTROL UNIT".
WJIA0436E
MJIB0194E

MTC-72
TROUBLE DIAGNOSIS
SYSTEM DESCRIPTION
Component Parts
lFront air control
lBlower switch
lBlower motor resistor
lBlower motor
lBlower motor relay
System Operation
Blower Speed Control Specification
COMPONENT DESCRIPTION
Blower Motor Resistor
The blower motor resistor is located on the cooling unit. The blower
motor resistor grounds the blower motor through a series of 1, 2, or
three resistors, depending upon speed selected. For high speed
operation the blower motor resistor is circumvented and the blower
motor grounds directly.
NOTE:
This illustration is for LHD models.
The layout for RHD models is symmetrically opposite.
MJIB0324E
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MJIB0195E

TROUBLE DIAGNOSIS
MTC-75
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MTC
9.CHECK BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT
1. Disconnect blower motor harness connector.
2. Check continuity between blower motor harness connector M94
terminal 2 and ground.
OK or NG
OK >> Check blower motor. Refer toMTC-77, "Blower Motor".
NG >> Repair harness or connector.
10.CHECK BLOWER MOTOR RELAY (SWITCH SIDE) POWER SUPPLY CIRCUIT
1. Disconnect blower motor harness connector.
2. Check continuity between blower motor relay harness connector
E28 terminal 5 and 7 and blower motor harness connector M94
terminal 2.
OK or NG
OK >> Repair harness or connector between blower motor
fuses and blower motor relay.
NG >> Repair harness or connector between blower motor
relay and blower motor.
11 .CHECK BLOWER MOTOR
Refer toMTC-77, "
Blower Motor".
OK or NG
OK >> GO TO 12.
NG >> Replace blower motor.
12.CHECK BLOWER SWITCH
Refer toMTC-77, "
Blower Switch".
OK or NG
OK >> Repair harness or connector between blower switch and blower motor.
NG >> Replace front air control. Refer toMTC-98, "
CONTROL UNIT".
13.CHECK BLOWER MOTOR RESISTOR
Refer toMTC-78, "
Blower Motor Resistor".
OK or NG
OK >> GO TO 14.
NG >> Replace blower motor resistor. Refer toMTC-112, "
BLOWER MOTOR RESISTOR". 2 - Ground : Continuity should not exist.
WJIA0649E
5, 7 - 2 : Continuity should exist.
MJIB0067E

MTC-76
TROUBLE DIAGNOSIS
14.CHECK BLOWER SWITCH CIRCUIT
1. Reconnect blower motor resistor harness connector.
2. Check voltage between blower switch connector M59 terminals
2, 3, and 7 and ground.
OK or NG
OK >> Replace front air control. Refer toMTC-98, "CONTROL UNIT".
NG >> GO TO 15.
15.CHECK BLOWER MOTOR GROUND CIRCUIT TO BLOWER MOTOR RESISTOR
1. Disconnect blower motor and blower motor resistor harness
connector.
2. Check continuity between blower motor connector M94 terminal
1 and blower motor resistor harness connector M95 terminal 3.
3. Check continuity between blower motor connector M94 terminal
1 and ground.
OK or NG
OK >> INSPECTION END.
NG >> Repair harness or connector.
16.CHECK BLOWER SWITCH
Refer toMTC-77, "
Blower Switch".
OK or NG
OK >> Repair harness or connector.
NG >> Replace front air control. Refer toMTC-98, "
CONTROL UNIT".
Terminal No.
Voltage
(Approx.)
+-
2
Ground 12V 3
7
M J I B 0 111 E
1 - 3 : Continuity should exist.
1 - Ground : Continuity should not exist.
WJIA0647E

MTC-82
TROUBLE DIAGNOSIS
6.CHECK CIRCUIT CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect BCM connector and front air control connector.
3. Check continuity between BCM harness connector M42 terminal
27 and front air control harness connector M98 terminal 10.
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.
7.CHECK VOLTAGE FOR FRONT AIR CONTROL (COMPRESSOR ON SIGNAL)
1. Reconnect BCM connector and front air control connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M98
terminal 10 and ground.
OK or NG
OK >> GO TO 8.
NG-1 >> If the voltage is approx. 5V when A/C switch is ON, replace front air control. Refer toMTC-98,
"CONTROL UNIT".
NG-2 >> If the voltage is approx. 0V when A/C switch is OFF, replace BCM. Refer toBCS-17, "
Removal
and Installation of BCM". 27 - 10 Continuity should exist.
MJIB0107E
Terminals
Condition Voltage (+)
(-) Front air
control con-
nectorTerminal No.
M98 10 GroundA/C switch: ON Approx. 0V
A/C switch: OFF Approx. 5V
WJIA1137E

MTC-84
TROUBLE DIAGNOSIS
10.CHECK CIRCUIT CONTINUITY BETWEEN BCM, FRONT AIR CONTROL AND BLOWER SWITCH
1. Turn ignition switch OFF.
2. Disconnect BCM connector and front air control connector and
blower switch.
3. Check continuity between BCM harness connector M42 terminal
26 and blower switch M59 terminal 2 and between front air con-
trol harness connector M98 terminal 18 and blower switch M59
terminal 8.
OK or NG
OK >> GO TO 11.
NG >> Repair harness or connector.
11 .CHECK VOLTAGE FOR BCM(FAN ON SIGNAL) AND FRONT AIR CONTROL(BLOWER MONITOR
SIGNAL)
1. Reconnect BCM connector and front air control connector and
blower switch.
2. Turn ignition switch ON.
3. Check voltage between the following terminals.
OK or NG
OK >> GO TO 12.
NG-1 >> If the voltage is approx.12V when blower motor is ON,
replace blower switch. Refer toMTC-98, "
CONTROL
UNIT".
NG-2 >> If the voltage is approx. 0V when blower motor is OFF,
replace BCM. Refer toBCS-17, "
Removal and Installa-
tion of BCM".
NG-3 >> If the voltage is less than 12V when blower motor is ON, replace front air control. Refer toMTC-
98, "CONTROL UNIT". 26 - 2 Continuity should exist.
18 - 8 Continuity should exist.
MJIB0109E
Terminals
Condition Voltage (+)
(-)
Connector Terminal No.
BCM
M4226
GroundA/C switch: ON
Blower motor
operatesApprox. 0V
A/C switch: OFF Approx. 12V
Front air control
M9818A/C switch: ON
Blower motor
operatesLess than
12V
MJIB0110E