DESCRIPTION This DTC is
stored if refrigerant pressure on the high pressure side is extremely
low (176 kPa (1.8 kgf/cm2, 26 psi) or less) or extremely high (3025 kPa
(30.8 kgf/cm2, 439 psi) or more). The air conditioner pressure sensor,
which is installed to the high pressure side pipe to detect refrigerant
pressure, sends a refrigerant pressure signal to the air conditioning
amplifier assembly. The air conditioning amplifier assembly converts
this signal to a pressure value according to the sensor characteristics
and uses it to control the compressor. |
DTC No. | Detection Item |
DTC Detection Condition | Trouble Area |
Memory | | B1423 |
Open in Pressure Sensor Circuit / Abnormal Refrigerant Pressure |
- Open or short in air conditioner pressure sensor circuit
- Refrigerant pressure on high pressure side is extremely low (176 kPa
(1.8 kgf/cm2, 26 psi) or less) or extremely high (3025 kPa (30.8
kgf/cm2, 439 psi) or more)
|
- Air conditioner pressure sensor
- Harness or connector
- Air conditioning amplifier assembly
- Cooler expansion valve (blocked, stuck)
- Cooler condenser assembly (blocked, deterioration of cooling capacity due to dirt)
- Cooler dryer (moisture in the refrigerant cycle cannot be absorbed)
- Cooling fan system (cooler condenser assembly cannot be cooled down)
- Air conditioning system (leaks, blocked)
- Refrigerant volume (excessive, low)
| - | WIRING DIAGRAM
 CAUTION / NOTICE / HINT
HINT: If DTC B1423 and B14B8 are output at the same time, troubleshoot for DTC B14B8 first.
Click here  PROCEDURE
| 1. |
PERFORM REFRIGERANT SHORTAGE CHECK | (a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG). (c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Air Conditioner / Utility / Refrigerant Gas Volume Check. Body Electrical > Air Conditioner > Utility
|
Tester Display | | Refrigerant Gas Volume Check |
(e)
Check that the following conditions are met and perform the refrigerant
shortage check according to the display on the Techstream. Measurement Condition: |
Item | Condition | |
A/C switch | On | |
Ambient temperature* |
0 to 49°C (32 to 120°F) | |
Blower speed | HI |
*: If the ambient temperature is not within the range shown, do not perform this check. |
Result | Amount of Refrigerant | |
Refrigerant correct | Correct | |
Refrigerant shortage |
Insufficient | OK: "Refrigerant correct" is displayed on the Techstream.
| NG |
 | GO TO STEP 14 |
|
OK |
 | |
| 2. |
CHECK REFRIGERANT PRESSURE | (a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG). (c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Air Conditioner / Data List.
(e) Read the Data List according to the display on the Techstream. Body Electrical > Air Conditioner > Data List
|
Tester Display | Measurement Item |
Range | Normal Condition |
Diagnostic Note | |
Regulator Pressure Sensor |
Air conditioner pressure sensor |
Min.: -66.2 psi (gauge) Max.: 478.0 psi (gauge) |
Actual refrigerant pressure displayed |
- Refrigerant line (gas leak etc.)
- Air conditioner pressure sensor circuit malfunction
| Body Electrical > Air Conditioner > Data List
|
Tester Display | | Regulator Pressure Sensor |
(f) Install a manifold gauge set. Click here
(g) Read the manifold gauge set with the following conditions met. Measurement Condition: |
Item | Condition | |
Vehicle doors | Fully open | |
Temperature setting | MAX COLD | |
Blower speed | HI | |
A/C switch | On | |
Recirculation/fresh switch |
RECIRCULATION | |
Interior temperature |
25 to 35°C (77 to 95°F) | Standard Pressure:
Low pressure side 150 to 250 kPa (1.5 to 2.5 kgf/cm2, 22 to 36 psi)
High pressure side 1370 to 1570 kPa (14 to 16 kgf/cm2, 199 to 228 psi)
(h) Compare the values displayed in the Data List and on the manifold gauge set.
OK: The values displayed in the Data List and on the manifold gauge set match.
| NG |
| GO TO STEP 8 |
|
OK | |
| |
| 3. |
CHECK REFRIGERANT HIGH PRESSURE HISTORY |
(a) Connect the Techstream to the DLC3. (b) Turn the engine switch on (IG).
(c) Enter the following menus: Body Electrical / Air Conditioner / Data List.
(d) Read the Data List according to the display on the Techstream. Body Electrical > Air Conditioner > Data List
|
Tester Display | Measurement Item |
Range | Normal Condition |
Diagnostic Note | |
Refrigerant High Pressure History |
Refrigerant high pressure history |
Min.: 0 Max.: 255 |
Number of times refrigerant high pressure history stored displayed |
- | Body Electrical > Air Conditioner > Data List
|
Tester Display | | Refrigerant High Pressure History |
|
Result | Proceed to | |
The value is 0 | A | |
The value is not 0 | B |
| A |
| INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET |
|
B | |
| |
| 4. |
INSPECT COOLING FAN SYSTEM | (a) Check if the cooling fan operates normally.
Click here
| NG |
| GO TO COOLING FAN SYSTEM |
|
OK | |
| |
| 5. |
RECOVER REFRIGERANT FROM REFRIGERATION SYSTEM |
(a) Recover the refrigerant from the air conditioning system using a refrigerant recovery unit.
Click here
|
NEXT | |
| |
| 6. |
CHARGE AIR CONDITIONING SYSTEM WITH REFRIGERANT |
Click here
|
NEXT | |
| |
| 7. |
PERFORM REFRIGERANT HIGH PRESSURE HISTORY CLEAR |
(a) Clear the refrigerant high pressure history stored in the air conditioning amplifier assembly.
Click here
| NEXT |
| END |
| 8. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) |
|
*a | Front view of wire harness connector
(to Air Conditioner Pressure Sensor) | (a) Disconnect the A15 air conditioner pressure sensor connector.
(b) Measure the voltage according to the value(s) in the table below. Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
A15-3 (+) - A15-1 (-) |
Engine switch on (IG) |
4.75 to 5.25 V |
| NG |
| GO TO STEP 13 |
|
OK | |
| |
| 9. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - BODY GROUND) |
|
*a | Front view of wire harness connector
(to Air Conditioner Pressure Sensor) | (a) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
A15-1 (-) - Body ground |
Always | Below 1 Ω |
| NG |
| GO TO STEP 12 |
|
OK | |
| |
| 10. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER ASSEMBLY) |
(a) Disconnect the G36 air conditioning amplifier assembly connector. (b) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
A15-2 (PR) - G36-24 (PRE) |
Always | Below 1 Ω | |
A15-2 (PR) or G36-24 (PRE) - Other terminals and body ground |
Always | 10 kΩ or higher |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
OK | |
| |
| 11. |
INSPECT AIR CONDITIONER PRESSURE SENSOR (SENSOR SIGNAL CIRCUIT) |
|
*a | Component with harness connected
(Air Conditioning Amplifier Assembly) |
(a) Measure the voltage with the following conditions met. Measurement Condition: |
Item | Condition | |
Vehicle doors | Fully open | |
Temperature setting | MAX COLD | |
Blower speed | HI | |
A/C switch | On | |
Recirculation/fresh switch |
RECIRCULATION | |
Interior temperature |
25 to 35°C (77 to 95°F) |
NOTICE:
- If refrigerant pressure on the high pressure side becomes extremely high
during the inspection (if the voltage exceeds 4.61 V), a fail-safe
function will stop compressor operation. In this case, make sure to
measure the voltage before the fail-safe function operates.
- It is necessary to measure the voltage for a certain amount of time
(approximately 10 minutes) because the malfunction may recur after a
while.
HINT: When the
ambient air temperature is low(below -1.5°C (29.3°F)), the compressor
with pulley will be stopped, due to inputs of the thermistor assembly
and No. 1 cooler thermistor, to prevent the evaporator from freezing. In
this case, perform the inspection in a warm indoor environment. (1) Measure the voltage according to the value(s) in the table below.
Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
G36-24 (PRE) - Body ground |
Engine switch on (IG) (A/C switch: On) |
0.74 to 4.61 V | (b) Connect the Techstream to the DLC3.
(c) Turn the engine switch on (IG). (d) Turn the Techstream on.
(e) Enter the following menus: Body Electrical / Air Conditioner / Data List.
(f) Read the Data List according to the display on the Techstream. Body Electrical > Air Conditioner > Data List
|
Tester Display | Measurement Item |
Range | Normal Condition |
Diagnostic Note | |
Regulator Pressure Sensor |
Air conditioner pressure sensor |
Min.: -66.2 psi (gauge) Max.: 478.0 psi (gauge) |
Actual refrigerant pressure displayed |
- Refrigerant line (gas leak etc.)
- Air conditioner pressure sensor circuit malfunction
| Body Electrical > Air Conditioner > Data List
|
Tester Display | | Regulator Pressure Sensor |
OK: The voltage and value displayed in the Data List change.
|
Result | Proceed to | |
OK | A | |
NG (The voltage changes but the value displayed in the Data List does not change.) | |
NG (The voltage does not change.) |
B |
| A |
| REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
| B |
| REPLACE AIR CONDITIONER PRESSURE SENSOR |
| 12. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER ASSEMBLY) |
(a) Disconnect the G36 air conditioning amplifier assembly connector. (b) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
A15-1 (-) - G36-3 (SG-4) |
Always | Below 1 Ω | |
A15-1 (-) or G36-3 (SG-4) - Other terminals and body ground |
Always | 10 kΩ or higher |
| OK |
| REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
| 13. |
CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER ASSEMBLY) |
(a) Disconnect the G36 air conditioning amplifier assembly connector. (b) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
A15-3 (+) - G36-6 (S5-3) |
Always | Below 1 Ω | |
A15-3 (+) or G36-6 (S5-3) - Other terminals and body ground |
Always | 10 kΩ or higher |
| OK |
| REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
| 14. |
REPAIR AIR CONDITIONING SYSTEM LEAK | (a) Identify the area where refrigerant is leaking from.
Click here (b) Repair the identified area of the air conditioning system.
(c) Evacuate the air conditioning system.
| NEXT |
| CHARGE SYSTEM WITH REFRIGERANT | | 
