Nissan Sentra Service Manual: Heating and cooling unit assembly
Exploded view
With air conditioning
- Defroster seal
- Center ventilator seal
- Upper distribution module
- Side ventilator seal (LH)
- Blower motor
- Blower unit
- Intake door motor
- Power transistor
- Power transistor wiring harness
- Front floor duct (lh)
- Vent and defroster linkage
- Mode door motor
- Heater core
- Heater core pipes grommet
- Heating and cooling unit
- In-cabin microfilter
- In-cabin microfilter cover
- Air mix door motor (lh) (automatic a/c only)
- Vent and defroster linkage
- Front floor duct (rh)
- Air mix door motor (RH)
- Expansion valve
- Evaporator
- Aspirator (automatic a/c only)
- Vent and defroster linkage
- Side ventilator seal (rh)
Without air conditioning
- Defroster seal
- Center ventilator seal
- Upper distribution module
- Side ventilator seal (lh)
- Blower motor
- Blower unit
- Intake door motor
- Power transistor
- Power transistor wiring harness
- Front floor duct (LH)
- Vent and defroster linkage
- Mode door motor
- Heater core
- Heater core pipes grommet
- Heating and cooling unit
- In-cabin microfilter
- In-cabin microfilter cover
- Front floor duct (RH)
- Air mix door motor
- Vent and defroster linkage
- Side ventilator seal (RH)
Heating and cooling unit assembly
Heating and cooling unit assembly :
removal and installation
NOTE:
When removing components such as hoses, lines/tubes, etc., cap or plug
openings to prevent fluid from spilling.
REMOVAL
- Discharge the refrigerant. Refer to HA-23, "Recycle Refrigerant".
- Drain the cooling system. Refer to CO-12, "Changing Engine Coolant".
- Remove the instrument panel assembly. Refer to IP-14, "Removal and
Installation".
- Remove the steering column. Refer to ST-12, "Removal and Installation".
- Remove the center console. Refer to IP-17, "Removal and Installation".
- Remove the wiper drive assembly. Refer to WW-62, "Removal and
Installation".
- Remove the steering member bolt (A).
(1): Windshield glass
NOTE:
The steering member bolt (A) can be found near the drivers side
cowl area in the engine compartment.

- Remove the push nut (A) from the expansion valve insulator (1)
and reposition.

- Remove the bolt (A) that retains the low-pressure flexible hose
and high-pressure pipe to the expansion valve.
CAUTION:
Cap or wrap the joint of the pipe with suitable material such
as vinyl tape to avoid the entry of air.

- Disconnect the low-pressure pipe and high-pressure pipe from the
expansion valve.
- Disconnect the heater hoses from the heater core pipes.
- Remove the remaining steering member bolts.
- Disconnect the harness connectors from the heating and cooling unit
assembly and steering member.
- Remove the heating and cooling unit assembly and steering member as an
assembly from the vehicle.
- Separate the heating and cooling unit assembly from the steering member.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
- Do not reuse O-rings.
- Apply A/C oil to new O-rings for installation.
- After charging refrigerant, check for leaks. Refer to HA-21, "Leak
Test".
Heater core
Heater core : removal and installation
REMOVAL
The heater core is not serviced separately and must be replaced with the
heating and cooling unit assembly.
Refer to HA-43, "HEATING AND COOLING UNIT ASSEMBLY : Removal and Installation".
Evaporator
Evaporator : removal and installation
REMOVAL
The evaporator is not serviced separately and must be replaced with the
heating and cooling unit assembly.
Refer to HA-45, "EVAPORATOR : Removal and Installation".
Expansion valve
Expansion valve : removal and installation
REMOVAL
- Discharge the refrigerant. Refer to HA-23, "Recycle Refrigerant".
- Remove the push nut (A) from the expansion valve insulator (1)
and reposition.

- Remove the bolt (A) that retains the low-pressure flexible hose
and high-pressure pipe to the expansion valve.

- Disconnect the low-pressure pipe and high-pressure pipe from the
expansion valve.
- Remove the expansion valve bolts.
- Remove the expansion valve.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
- Do not reuse O-rings.
- Apply A/C oil to the new expansion valve O-rings for installation.
- After charging refrigerant, check for leaks. Refer to HA-21, "Leak
Test".
Exploded view
Core support upper cover
High-pressure pipe
High-pressure flexible hose
Refrigerant pressure sensor
Condenser and liquid tank assembly
Core support upper
Front
Conde ...
Service Data and Specification (SDS)
COMPRESSOR
OIL
REFRIGERANT
...
Other materials:
P0300, P0301, P0302, P0303, P0304 Misfire
DTC Logic
DTC DETECTION LOGIC
When a misfire occurs, engine speed will fluctuate. If the engine speed
fluctuates enough to cause the crankshaft
position (CKP) sensor (POS) signal to vary, ECM can determine that a misfire is
occurring.
Sensor
Input signal to ECM
ECM function
...
Precaution
Precaution for supplemental restraint system (srs) "air bag" and "seat belt
pre-tensioner"
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”,
used along
with a front seat belt, helps to reduce the risk or severity of injur ...
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”,
used along
with a front seat belt, helps to reduce the risk or severity of injury to the
driver and front passenger for certain
types of collision. Information necessary to service the system ...
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