ECU NISSAN PATROL 1998 Y61 / 5.G Heather And Air Conditioner Workshop Manual

Operation
The auto ampli®er receives data from each of the sensors. The ampli®er sends air mix door and mode door
opening angle data to the air mix door motor LCU and mode door motor LCU.
The air mix door motor and mode door motor read their respective signals according to the address signal.
Opening angle indication signals received from the auto ampli®er and each of the motor position sensors are
compared by the LCUs in each motor with the existing decision and opening angles. Subsequently, HOT/
COLD or DEFROST/VENT operation is selected. The new selection data is returned to the auto ampli®er.
Transmission data and transmission order
Ampli®er data is transmitted consecutively to each of the door motors following the form shown in ®gure below.
Start: Initial compulsory signal sent to each of the door motors.
Address: Data sent from the auto ampli®er is selected according to data-based decisions made by the air mix
door motor and mode door motor.
If the addresses are identical, the opening angle data and error check signals are received by the door motor
LCUs. The LCUs then make the appropriate error decision. If the opening angle data is normal, door control
begins.
If an error exists, the received data is rejected and corrected data received. Finally, door control is based upon
the corrected opening angle data.
Opening angle: Data that shows the indicated door opening angle of each door motor.
Error check: Procedure by which sent and received data is checked for errors. Error data is then compiled.
The error check prevents corrupted data from being used by the air mix door motor and mode door motor.
Error data can be related to the following problems.
+Abnormal electrical frequency
+Poor electrical connections
+Signal leakage from transmission lines
+Signal level ¯uctuation
Stop signal: At the end of each transmission, a stop operation, in-operation, or internal problem message is
delivered to the auto ampli®er. This completes one data transmission and control cycle.
RHA441GA
DESCRIPTIONAUTO
Features (Cont'd)
HA-50

Air mix door control speci®cation
COMPONENT DESCRIPTION
The air mix door motor is attached to the heater unit. It rotates so
that the air mix door is opened or closed to a position set by the
auto ampli®er. Motor rotation is then conveyed through a shaft and
the air mix door position is then fed back to the auto ampli®er by
PBR built-in air mix door motor.
CONTROL LINKAGE ADJUSTMENT
Air mix door (Water cock)
1. Install air mix door motor on heater unit and connect it to main
harness.
2. Set up code No.
in Self-diagnosis STEP 4. Refer to HA-67.
3. Move air mix door lever by hand and hold it in full cold position.
4. Attach air mix door lever to rod holder.
5. Make sure air mix door operates properly when changing from
code No.
toby pushing DEF switch.
Full cold Full hot
6. Set up code No.in Self-diagnosis STEP 4.
7. Attach water cock cable to air mix door linkage and secure with
clip.
8. Rotate and hold water cock lever AND plate in the full cold
position (CLOCKWISE completely).
9. Attach water cock cable to plate and secure with clip (white
mark on cable housing should be centered under the retaining
clip).
10. Check that water cock operates properly when changing from
code No.
toby pushing DEF switch. (After several
cycles, water cock lever should be midpoint of plate opening
when code No.
is set.)
RHA690G
RHA696G
SHA522E
TROUBLE DIAGNOSESAUTO
Air Mix Door Motor (Cont'd)
HA-81

3. Move probe along component approximately 25 to 50 mm (1 to
2 in)/sec.
CHECKING PROCEDURE
To prevent inaccurate or false readings, make sure there is no
refrigerant vapor or tobacco smoke in the vicinity of the
vehicle. Perform the leak test in calm area (low air/wind move-
ment) so that the leaking refrigerant is not dispersed.
1. Turn engine off.
2. Connect a suitable A/C manifold gauge set to the A/C service
ports.
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.452
bar, 3.52 kg/cm
2, 50 psi) above 16ÉC (61ÉF). If less than
speci®cation, evacuate and recharge the system with the speci-
®ed amount of refrigerant.
NOTE: At temperatures below 16ÉC (61ÉF), leaks may not be
detected since the system may not reach 345 kPa
(3.452 bar, 3.52 kg/cm
2, 50 psi).
4. Conduct the leak test from the high side to the low side at points
in alphabetical order (j
a,jb......). Refer to HA-117.
Perform a leak check for the following areas carefully. Clean the
component to be checked and move the leak detector probe
completely around the connection/component.
+Compressor
Check the ®tting of high and low pressure hoses, relief valve
and shaft seal.
+Liquid tank
Check the pressure switch, tube ®tting, weld seams and the
fusible plug mounts.
+Service valves
Check all around the service valves. Ensure service valve caps
are secured on the service valves (to prevent leaks).
NOTE: After removing A/C manifold gauge set from service
valves, wipe any residue from valves to prevent any
false readings by leak detector.
+Cooling unit (Evaporator)
Turn blower fan on ``High'' for at least 15 seconds to dissipate
any refrigerant trace in the cooling unit. Insert the leak detector
probe into the drain hose immediately after stopping the
engine. (Keep the probe inserted for at least ten seconds.)
5. If a leak detector detects a leak, verify at least once by blowing
compressed air into area of suspected leak, then repeat check.
6. Do not stop when one leak is found. Continue to check for
additional leaks at all system components.
7. Start engine.
8. Set the heater A/C control as follows:
a. A/C switch ON
b. Face mode
c. Recirculation switch ON
d. Max cold temperature
e. Fan speed high
SHA708EA
SERVICE PROCEDURESMANUAL AND AUTO
Checking Refrigerant Leaks (Cont'd)
HA-120