DESCRIPTION This DTC is stored if the amount of refrigerant in the air conditioning system is insufficient.
The
air conditioning amplifier assembly receives the ambient temperature
signal, refrigerant pressure signal, etc. from various sensors. Based on these signals, the air conditioning amplifier assembly detects the amount of refrigerant.
If
the amount of refrigerant is insufficient, the A/C switch indicator
will turn off and the air conditioning system will stop operating. |
DTC No. | Detection Item |
DTC Detection Condition | Trouble Area |
Memory | | B14B8 |
Refrigerant Shortage | The following condition is detected in the normal operation refrigerant shortage check:
Amount of refrigerant is insufficient |
- Refrigerant line
- Cooler expansion valve
- Air conditioning amplifier assembly
- Harness or connector
- Air conditioner pressure sensor
| Memorized (10 min. or more)* |
- *: The air conditioning amplifier assembly stores this DTC if the
malfunction has occurred for the period of time indicated in the
brackets.
WIRING DIAGRAM
 PROCEDURE
| 1. |
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 |
30 to 35°C (86 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.
| OK |
 | INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET |
|
NG |
 | |
| 2. |
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 (+) - Body ground |
Engine switch on (IG) |
4.75 to 5.25 V |
| NG |
| GO TO STEP 7 |
|
OK | |
| |
| 3. |
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 6 |
|
OK | |
| |
| 4. |
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 | |
| |
| 5. |
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 |
| 6. |
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 |
| 7. |
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 | | 
