ON-VEHICLE INSPECTION
PROCEDURE
1. INSPECT REFRIGERANT PRESSURE
(a) This method uses a refrigerant recovery unit set to locate problem areas. Read the refrigerant pressure when the test conditions are established.
Test conditions:
Gauge readings (Reference):
Text in Illustration
*a |
Pressure on low-pressure side |
*b |
Blower HI Zone |
*c |
Blower LO Zone |
*d |
Pressure on high-pressure side |
(1) Normally functioning refrigeration system. Gauge Reading:
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|
(2) The A/C system periodically changes between normal and improper function due to moisture in the refrigerant system.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
During operation, pressure on low pressure side cycles between normal and vacuum |
Moisture in refrigeration system freezes at expansion valve orifice, causing temporary stop of cycle. However, when melted, normal state is restored. |
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|
(3) The A/C system does not function effectively due to insufficient refrigerant.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
|
Gas leakage from refrigeration system |
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|
(4) The A/C system does not function effectively due to poor circulation of the refrigerant.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
|
Refrigerant flow obstructed by dirt in condenser |
Condenser clogged |
Replace condenser |
(5) The A/C system does not function or functions intermittently because the refrigerant does not circulate.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
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|
Refrigerant does not circulate |
|
(6) The A/C system does not function effectively due to the system being overcharged with refrigerant or insufficient cooling of the condenser.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
Pressure extremely high on both low and high-pressure sides |
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|
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(7) The A/C system does not function due to air in the refrigeration system.
CAUTION:
The low-pressure piping may be very hot and cause serious burns.
NOTICE:
These gauge indications occur when the refrigeration system opens and the system is charged with refrigerant without vacuum purging.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
|
Air in refrigeration system |
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|
(8) The A/C system does not function effectively due to an expansion valve malfunction.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
|
Problem with expansion valve |
|
Replace expansion valve |
(9) The A/C system does not function due to a defective compressor.
Text in Illustration
*a |
Low Pressure Side |
*b |
High Pressure Side |
Symptom |
Probable Cause |
Diagnosis |
Corrective Action |
---|---|---|---|
|
Internal leakage in compressor |
|
Repair or replace compressor |
Removal
REMOVAL
PROCEDURE
1. PRECAUTION
NOTICE:
After turning the ignition switch off, waiting time may be required before disconnecting
the cable from the negative (-) battery terminal. Therefore, make sure to read the
disconnecting the cable from the negative (-) battery terminal notices before pr ...
Communication Malfunction between ECUs Connected by LIN (B2785)
DESCRIPTION
The certification ECU (smart key ECU assembly) monitors communication between
all the ECUs connected to the certification bus lines. When the certification ECU
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Data List / Active Test
DATA LIST / ACTIVE TEST
NOTICE:
In the table below, the values listed under "Normal Condition" are reference
values. Do not depend solely on these reference values when deciding whether a part
is faulty or not.
HINT:
Using the Techstream to read the Data List allows the values or s ...