NISSAN NAVARA 2005 Repair Workshop Manual

MTC-54
TROUBLE DIAGNOSIS
CHECKING TEMPERATURE DECREASE
1. Rotate temperature dial counterclockwise.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation if OK, go to
trouble diagnosis procedure forMTC-86, "
Insufficient Cooling".Ifair
mix door motor appears to be malfunctioning, go toMTC-63, "
Air Mix
Door Motor Circuit".
If OK, continue with next check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature dial clockwise.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to
trouble diagnosis procedure forMTC-93, "
Insufficient Heating".Ifair
mix door motor appears to be malfunctioning, go toMTC-63, "
Air Mix
Door Motor Circuit".
If OK, continue with next check.
CHECK A/C SWITCH
1. Press A/C switch with the blower switch ON.
2. A/C switch indicator will turn ON.
lConfirm that the compressor clutch engages (sound or visual
inspection).
If NG, go to trouble diagnosis procedure forMTC-79, "
Magnet Clutch
Circuit".
If OK, continue with next check.
MJIB0226E
MJIB0227E
MJIB0228E

TROUBLE DIAGNOSIS
MTC-55
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MTC
Power Supply and Ground Circuit for Front Air ControlEJS005GD
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
*1MTC-55, "Power Supply and Ground
Circuit for Front Air Control".*2MTC-53, "
Operational Check"
MJIB0229E

MTC-56
TROUBLE DIAGNOSIS
COMPONENT DESCRIPTION
Front Air Control
The front air control has a built-in microcomputer which processes
information sent from various sensors needed for air conditioner
operation. The air mix door motors, mode door motor, intake door
motors, defroster door motor, blower motor and compressor are then
controlled.
The front air control is unitized with control mechanisms. When the
various switches and temperature dials are operated, data is input to
the front air control.
Self-diagnostic functions are also built into the front air control to pro-
vide quick check of malfunctions (NAVI equipped vehicles only).
Potentio Temperature Control (PTC)
The PTC is built into the front air control. It can be set from cold to
hot or any intermediate position by rotating the temperature dial.
DIAGNOSTIC PROCEDURE FOR A/C SYSTEM
SYMPTOM: A/C system does not come on.
MJIB0320E
MJIB0230E
MJIB0190E

TROUBLE DIAGNOSIS
MTC-57
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MTC
1.CHECK POWER SUPPLY CIRCUITS FOR FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect front air control connector.
3. Check voltage between front air control harness connector M98
terminals 6 and 19, and ground.
OK or NG
OK >> GO TO 2.
NG >> Check 10A fuses [Nos. 8 and 19, located in the fuse block (J/B)]. Refer toPG-83
.
lIf fuses are OK, check harness for open circuit. Repair or replace as necessary.
lIf fuses are NG, replace fuse and check harness for short circuit. Repair or replace as neces-
sary.
2.CHECK GROUND CIRCUIT FOR FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Check continuity between front air control harness connector
M98 terminal 20 and ground.
OK or NG
OK >> Replace front air control. Refer toMTC-98, "CONTROL
UNIT".
NG >> Repair harness or connector.
Terminals Ignition switch position
(+)
(-) OFF ACC ON Front air
control
connectorTerminal No.
M98 6
GroundApprox. 0V Approx. 0VBattery
voltage
M98 19Battery
voltageBattery
voltageBattery
voltage
WJIA1082E
20 - Ground : Continuity should exist.
WJIA1239E

MTC-58
TROUBLE DIAGNOSIS
Mode Door Motor Circuit
EJS005GE
SYMPTOM:
lAir outlet does not change.
lMode door motor does not operate normally.
INSPECTION FLOW
*1MTC-30, "Discharge Air Flow".*2MTC-53, "Operational Check".*3MTC-51, "A/C System Self-diagno-
sis Function".
*4MTC-52, "
SELF-DIAGNOSIS CODE
CHART".*5MTC-58, "
Mode Door Motor Circuit".
MJIB0289E

TROUBLE DIAGNOSIS
MTC-59
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MTC
SYSTEM DESCRIPTION
Component Parts
Mode door control system components are:
lFront air control
lMode door motor
lPBR (built into mode door motor)
System Operation
The mode door position (vent, B/L, foot, and defrost) is set by the front air control by means of the mode door
motor. When a mode door position is selected on the front air control, voltage is applied to one circuit of the
mode door motor while ground is applied to the other circuit, causing the mode door motor to rotate. The direc-
tion 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 mode door position by measuring the voltage signal on the PBR circuit.
Mode Door Control Specification
COMPONENT DESCRIPTION
Mode Door Motor
The mode door motor is attached to the heater & cooling unit. It
rotates so that air is discharged from the outlet as indicated by the
front air control. Motor rotation is conveyed to a link which activates
themodedoor.
NOTE:
This illustration is for LHD models.
The layout for RHD models is symmetrically opposite.
DIAGNOSTIC PROCEDURE FOR MODE 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 92 is present. Refer toMTC-51, "
A/C System Self-diagnosis Function".
YES or NO
YES >> GO TO 3.
NO >> GO TO 4.
WJIA0434E
MJIB0191E

MTC-60
TROUBLE DIAGNOSIS
3.CHECK POWER SUPPLY AND GROUND CIRCUITS FOR MODE DOOR MOTOR
1. Turn ignition switch OFF.
2. Disconnect front air control connector and mode door motor
connector.
3. Check continuity between front air control harness connector
M98 terminal 1 and mode door motor connector M46 terminal 1
and between front air control harness connector M98 terminal
14 and mode door motor connector M46 terminal 6.
OK or NG
OK >> Replace mode door motor.
NG >> Repair or replace harness as necessary.
4.CHECK PBR REFERENCE SIGNAL VOLTAGE
1. Turn ignition switch OFF.
2. Disconnect the mode door motor connector.
3. Turn ignition switch ON.
4. Check voltage between mode door motor harness connector
M46 terminal 3 and ground.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.1 - 1 : Continuity should exist.
14 - 6 : Continuity should exist.
MJIB0232E
3 - Ground : Approx. 5V
MJIB0233E

TROUBLE DIAGNOSIS
MTC-61
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MTC
5.CHECK PBR REFERENCE VOLTAGE CIRCUIT BETWEEN MODE DOOR AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect the front air control connector.
3. Check continuity between mode door motor harness connector
M46 terminal 3 and front air control harness connector M98 ter-
minal 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 mode door motor harness connector
M46 terminal 2 and front air control harness connector M98 ter-
minal 26.
OK or NG
OK >> GO TO 7.
NG >> Repair or replace harness as necessary.3 - 23 : Continuity should exist.
MJIB0234E
2 - 26 : Continuity should exist.
MJIB0235E

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

TROUBLE DIAGNOSIS
MTC-63
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MTC
Air Mix Door Motor CircuitEJS005GF
SYMPTOM:
lDischarge air temperature does not change.
lAir mix door motor does not operate.
INSPECTION FLOW
*1MTC-53, "Operational Check".*2MTC-51, "A/C System Self-diagno-
sis Function".*3MTC-52, "
SELF-DIAGNOSIS CODE
CHART".
*4MTC-64, "
DIAGNOSTIC PROCE-
DURE FOR AIR MIX DOOR
MOTOR (FRONT)".
MJIB0236E