Trouble Diagnosis For Unusual Pressure
Diagnose using a manifold gauge whenever system’s high and/or low side pressure(s) is/are unusual. The marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Refer to above table (Ambient air temperature-to-operating pressure table) since the standard (usual) pressure, however, differs from vehicle to vehicle.
Symptom Table
Gauge indication |
Refrigerant cycle |
Probable cause |
Corrective action |
Both high- and low-pressure sides
are too high.
|
The pressure returns to normal is reduced soon after water is splashed on condenser. | Excessive refrigerant charge in refrigeration cycle. | Reduce refrigerant until specified pressure is obtained. |
Air suction by cooling fan is insufficient. | Insufficient condenser cooling
performance.
↓
|
|
|
|
Poor heat exchange in condenser
(After compressor operation
stops, high-pressure decreases
too slowly). ↓ Air in refrigeration cycle. |
Evacuate repeatedly and recharge system. | |
Engine tends to overheat. | Engine cooling systems malfunction | Check and repair each engine cooling system. | |
|
↓ Improper expansion valve adjustment. |
Replace expansion valve. | |
High-pressure side is too high and
low-pressure side is too low.
|
Upper side of condenser and high-pressure side are hot, however, liquid tank is not so hot. | High-pressure tube or parts located between compressor and condenser are clogged or crushed |
|
High-pressure side is too low and
low-pressure side is too high.
|
High- and low-pressure sides become equal soon after compressor operation stops. | Compressor pressure operation
is improper. ↓ Damaged inside compressor packings. |
Replace compressor |
No temperature difference between high- and low-pressure sides. | Compressor pressure operation
is improper. ↓ Damaged inside compressor packings. |
Replace compressor. | |
Both high- and low-pressure sides
are too low.
|
|
Liquid tank inside is slightly clogged. |
|
|
High-pressure pipe located between liquid tank and expansion valve is clogged. |
|
|
Expansion valve and liquid tank are warm or slightly cool when touched. | Low refrigerant charge. ↓ Leaking fittings or components. |
Check refrigerant for leaks. Refer to HA-21, "Leak Test". | |
There is a big temperature difference between expansion valve inlet and outlet while the valve itself is frosted. | compared with the specification. ↓
|
|
|
An area of the low-pressure pipe is colder than areas near the evaporator outlet. | Low-pressure pipe is clogged or crushed. |
|
|
Air flow volume is not enough or is too low. | Evaporator is frozen. |
|
|
Low-pressure side sometimes becomes
negative.
|
|
Refrigerant does not discharge
cyclically. ↓ Moisture is frozen at expansion valve outlet and inlet. ↓ Water is mixed with refrigerant. |
|
Low-pressure side becomes negative.
|
Liquid tank or front/rear side of expansion valve’s pipe is frosted or wet with dew. | High-pressure side is closed
and refrigerant does not flow. ↓ Expansion valve or liquid tank is frosted. |
Leave the system at rest until
no frost is present. Start it again
to check whether or not the malfunction
is caused by water or
foreign particles.
|
System description
COMPONENT PARTS
Component Parts Location
Air bag diagnosis sensor unit
AV control unit
Around view monitor control unit
Chassis control module
ABS actuator and electric unit (control
unit)
• A/C auto amp. (With auto A/C)
• Front air control (Without auto A/
C)
...
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 injury to the
...
Front disc brake
BRAKE CALIPER ASSEMBLY (1 PISTON TYPE)
BRAKE CALIPER ASSEMBLY (1 PISTON TYPE) : Exploded View
Torque member
Bushing
Piston boot
Slide pin boot
Slide pin
Piston
Piston seal
Brake caliper body
Bleeder cap
Brake hose
Copper sealing washers
...