2003 NISSAN ALMERA N16 blower

ATC-70
TROUBLE DIAGNOSIS
SYSTEM DESCRIPTION
Component Parts
Fan speed control system components are:
●Auto amp.
●A/C LAN system (PBR built-in air mix door motor, mode door motor and intake door motor)
●Fan control amp.
●In-vehicle sensor
●Ambient sensor
●Sunload sensor
●Intake sensor
System Operation
Automatic Mode
In the automatic mode, the blower motor speed is calculated by the automatic amplifier based on input from
the PBR, in-vehicle sensor, sunload sensor, intake sensor and ambient sensor.
The blower motor applied voltage ranges from approximately 4 volts (lowest speed) to 12 volts (highest
speed).
The control blower speed (in the range of 4 to 12V), the automatic amplifier supplies a gate voltage to the fan
control amplifier. Based on this voltage, the fan control amplifier controls the voltage supplied to the blower
motor.
Starting Fan Speed Control
Start Up From COLD SOAK Condition (Automatic mode)
In a cold start up condition where the engine coolant temperature is below 56°C (133°F), the blower will not
operate for a short period of time (up to 150 seconds). The exact start delay time varies depending on the
ambient and engine coolant temperature.
*1AT C - 4 2 , "Self-diagnosis Function"*2AT C - 4 2 , "Self-diagnosis Function",
see No.14.*3AT C - 6 9 , "Blower Motor Circuit"
*4AT C - 5 1 , "Operational Check"*5AT C - 2 9 , "SYMPTOM TABLE"*6 QG engine (With EURO–OBD): EC-
144, "DTC P0117, P0118 ECT SEN-
SOR"
QG engine (Without EURO–OBD):
EC-501, "
DTC P0117, P0118 ECT
SENSOR"
YD engine: EC-84, "DTC 0115
COOLANT TEMP SEN"
RJIA0785E

TROUBLE DIAGNOSIS
ATC-71
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AT C
In the most extreme case (very low ambient) the blower starting delay will be 150 seconds as described
above. After this delay, the blower will operate at low speed until the engine coolant temperature rises above
56°C (133°F), at which time the blower speed will increase to the objective speed.
Start Up From Usual or HOT SOAK Condition (Automatic mode)
The blower will begin operation momentarily after the A/C button is pushed. The blower speed will gradually
rise to the objective speed over a time period of 3 seconds or less (actual time depends on the objective
blower speed).
Blower Speed Compensation
Sunload
When the in-vehicle temperature and the set temperature are very close, the blower will be operating at low
speed. The low speed will vary depending on the sunload. During conditions of low or no sunload, the blower
low speed is usual low speed (approx. 4V). During high sunload conditions, the auto amp causes the blower
fan speed to increase.(Approx. 7V)
Fan Speed Control Specification
COMPONENT DESCRIPTION
Fan Control Amplifier
The fan control amplifier is located on the heater & cooling unit. The
fan control amp. receives a gate voltage from the auto amp. to step-
lessly maintain the blower fan motor voltage in the 4 to 12 volt range.
DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR
SYMPTOM: Blower motor operation is malfunctioning under starting
fan speed control.
RJIA0522E
RHA625H
RJIA0786E

ATC-72
TROUBLE DIAGNOSIS
1. CHECK POWER SUPPLY FOR BLOWER MOTOR
Disconnect blower motor harness connector.
OK or NG
OK >> GO TO 2.
NG >> Check power supply circuit and 15A fuses (Nos. 14 and
16, located in the fuse block). Refer to EL-11, "POWER
SUPPLY ROUTING".
●If OK, check for open circuit in wiring harness. Repair or replace as necessary.
●If NG, replace fuse and check wiring harness for short circuit. Repair or replace as necessary.
2. CHECK FAN FEED BACK CIRCUIT
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3. CHECK BLOWER MOTOR
Refer to COMPONENT INSPECTION.
OK or NG
OK >> GO TO 4.
NG >> Replace blower motor.
4. CHECK POWER SUPPLY FOR FAN CONTROL AMP.
1. Reconnect blower motor connector.
2. Disconnect fan control amp. harness connector.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
Terminal
Vo l ta g e (+)
(-)
Blower motor con-
nectorTerminal No.
(Wire color)
M59 1 (L/W) Ground Approx. 12V
RJIA0524E
Te r m i n a l
Condition Voltage (+)
(-)
Auto amp.
connectorTerminal No.
(Wire color)
M205 34 (L/B) Ground Fan speed: 1st Approx. 8V
RJIA0787E
Te r m i n a l
Voltag e (+)
(-)
Fan control amp.
connectorTerminal No.
(Wire color)
M190 3 (L/B) Ground Approx. 12V
RJIA0526E

ATC-74
TROUBLE DIAGNOSIS
9. CHECK CIRCUIT CONTINUITY BETWEEN AUTO AMP. AND FAN CONTROL AMP.
OK or NG
OK >> Replace auto amp.
NG >> Repair harness or connector.
COMPONENT INSPECTION
Blower Motor
Confirm smooth rotation of the blower motor.
●Ensure that there are no foreign particles inside the intake unit.
Te r m i n a l
Continuity (+) (-)
Auto amp.
connectorTerminal No.
(Wire color)Fan control
amp. Con-
nectorTe r m i n a l N o .
(Wire color)
M205 34 (L/B) M190 3 (L/B) Yes
RJIA0789E
RJIA0790E

TROUBLE DIAGNOSIS
ATC-79
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9.CHECK FAN ON SIGNAL
OK or NG
OK >> GO TO 10.
NG >>
●If the voltage is approx. 5V when the blower fan is
ON: Replace the auto amp.
●If the voltage is approx. 0V when the blower fan is OFF: GO TO 17.
10.CHECK COMPRESSOR ON SIGNAL
OK or NG
OK >> GO TO 11.
NG >>
●If the voltage is approx. 5V when the A/C switch is
ON: Replace the auto amp.
●If the voltage is approx. 0V when the A/C switch is OFF.
–With gasoline engine: GO TO 18.
–With diesel engine: GO TO 13.
11 . CHECK MULTIPLEX COMMUNICATION CIRCUIT
Refer to ATC-109, "
Multiplex Communication Circuit" .
OK or NG
OK >> GO TO 12.
NG >> Repair harness or connector.
12.CHECK CAN CIRCUIT
Refer to CAN communication. EL-509, "CAN COMMUNICATION".
OK or NG
OK >> INSPECTION END.
NG >> Repair or replace malfunctioning part(s).
Terminal
Condition Voltage (+)
(-)
Auto amp.
connectorTerminal No.
(Wire color)
M205 29 (LG/B) GroundBlower fan: ON Approx. 0V
Blower fan: OFF Approx. 5V
RJIA0797E
Terminal
Condition Voltage (+)
(-)
Auto amp.
connectorTerminal No.
(Wire color)
M205 22 (L/R) GroundA/C SW: ON Approx. 0V
A/C SW: OFF Approx. 5V
RJIA0798E

ATC-86
TROUBLE DIAGNOSIS
Insufficient Cooling
EJS001ZQ
SYMPTOM: Insufficient cooling
INSPECTION FLOW
*1ATC-42, "Self-diagnosis Function",
see No.1.*2ATC-63, "Air Mix Door Motor Circuit"*3ATC-90, "Test Reading (Gasoline
Engine)"
ATC-90, "Test Reading (Diesel
Engine)"
*4ATC-42, "Self-diagnosis Function",
see No.14.*5ATC-57, "LAN System Circuit"*6ATC-69, "Blower Motor Circuit"
RJIA1708E

TROUBLE DIAGNOSIS
ATC-89
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*1ATC-138, "Compressor Clutch"*2AT C - 6 9 , "Blower Motor Circuit"*3 QG engine: EM-11, "Checking Drive
Belts"
YD engine: EM-11, "DRIVE BELTS"
RJIA1595E

ATC-90
TROUBLE DIAGNOSIS
PERFORMANCE CHART
Test Condition
Testing must be performed as follows:
Test Reading (Gasoline Engine)
Recirculating-to-discharge Air Temperature Table
Ambient Air Temperature-to-operating Pressure Table
Test Reading (Diesel Engine)
Recirculating-to-discharge Air Temperature Table
Vehicle location Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door windows Open
Hood Open
TEMP. Max. COLD
Mode switch (Ventilation) set
Intake switch (Recirculation) set
(blower) speedMax. speed set
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements.
Inside air (Recirculating air) at blower assembly inlet
Discharge air temperature at center ventilator
°C (°F) Relative humidity
%Air temperature
°C (°F)
50 - 6025 (77) 10.0 - 11.6 (50 - 53)
30 (86) 13.9 - 16.2 (57 - 61)
35 (95) 17.8 - 21.4 (64 - 71)
60 - 7025 (77) 11.6 - 13.9 (53 - 57)
30 (86) 16.2 - 18.9 (61 - 66)
35 (95) 21.4 - 24.5 (71 - 76)
Ambient air
High-pressure (Discharge side)
kPa (bar, kg/cm
2 , psi)Low-pressure (Suction side)
kPa (bar, kg/cm2 , psi) Relative humidity
%Air temperature
°C (°F)
50 - 7030 (86)980 - 1,180
(9.8 - 11.8, 9.99 - 12.04, 142 - 171)230 - 270 (2.3 - 2.7, 2.35 - 2.75, 33 - 39)
35 (95)1,180 - 1,390
(11.8 - 13.9, 12.04 - 14.18, 171 - 202)260 - 310 (2.6 - 3.1, 2.65 - 3.16, 38 - 45)
40 (104)1,400 - 1,580
(14.0 - 15.8, 14.28 - 16.12, 203 - 229)300 - 350 (3.0 - 3.5, 3.06 - 3.57, 44 - 51)
Inside air (Recirculating air) at blower assembly inlet
Discharge air temperature at center ventilator
°C (°F) Relative humidity
%Air temperature
°C (°F)
50 - 6020 (68) 6.5 - 9.0 (44 - 48)
25(77) 12 - 14 (54 - 57)
30 (86) 15.5 - 18.8 (60 - 66)
35 (95) 20.4 - 24.0 (69 - 75)