Heater & Air Conditioning System. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
Air Conditioning. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
Air Conditioning System (For Automatic Air Conditioning System) -- Terminals Of Ecu |
CHECK AIR CONDITIONING AMPLIFIER |

Measure the voltage and resistance of the connectors.
- HINT:
- Check from the rear of the connector while it is connected to the air conditioning amplifier.
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition SOL+ (E41-2) - GND (E41-14) GR - W-B A/C compressor operation signal Engine idling Pulse generation
(see waveform 1)Refrigerant pressure: normal Always Blower switch LO A/C switch ON PRE (E41-9) - SG-2 (E41-13) L - G Air conditioning pressure sensor signal Refrigerant pressure: Abnormal (less than 0.196 MPa [2.0 kgf/cm2, 28 psi]) Below 0.76 V PRE (E41-9) - SG-2 (E41-13) L - G Air conditioning pressure sensor signal Refrigerant pressure: Abnormal (more than 3.14 MPa [32 kgf/cm2, 455 psi]) 4.74 V or higher BLW (E41-23) - GND (E41-14) R - W-B Blower motor control signal Ignition switch on (IG) Pulse generation
(see waveform 2)Blower switch LO TSD (E41-33) - S5-4 (E41-31) L - LG Driver side solar sensor signal Ignition switch on (IG) 0.8 to 4.3 V Solar sensor subject to electric light TSP (E41-32) - S5-4 (E41-31) P - LG Passenger side solar sensor signal Ignition switch on (IG) 0.8 to 4.3 V Solar sensor subject to electric light TR (E41-29) - SG-1 (E41-34) GR- V Room temperature sensor signal Ignition switch on (IG) 1.8 to 2.2 V Vehicle interior temperature: 25°C (77°F) SG-1 (E41-34) - Body ground V - Body ground Ground for room temperature sensor Always Below 1 V GND (E41-14) - Body ground W-B - Body ground Ground for main power supply Always Below 1 V IG+ (E41-1) - GND (E41-14) Y - W-B Power source (IG) Ignition switch on (IG) 10 to 14 V S5-3 (E41-10) - GND (E41-14) B - W-B Power supply for pressure sensor Ignition switch on (IG) 4.5 to 5.5 V CANH (E41-11) - GND (E41-14) V - W-B Hi-level CAN bus line Ignition switch on (IG) Pulse generation
(see waveform 3)CANL (E41-12) - GND (E41-14) W - W-B Lo-level CAN bus line Ignition switch on (IG) Pulse generation
(see waveform 4)RDEF (E41-38) - GND (E41-14) B - W-B Rear defogger switch signal Ignition switch on (IG)
Rear defogger switch OFF10 to 14 V RDEF (E41-38) - GND (E41-14) B - W-B Rear defogger switch signal Ignition switch on (IG)
Rear defogger switch ONBelow 1 V SG-2 (E41-13) - Body ground G - Body ground Ground for pressure sensor Always Below 1 V PTC1 (E41-3) - Body ground(*1) W - Body ground PTC NO. 1 heater relay operation signal Engine idling Below 1 V → 10 to 14 V Set temperature: MAX HOT Engine coolant temperature: Below 65°C (149°F) Ambient temperature: Below 10°C (50°F) Light control switch: OFF Blower switch OFF → LO PTC2 (E41-22) - Body ground(*1) B - Body ground PTC NO. 2 heater relay operation signal Engine idling Below 1 V → 10 to 14 V Set temperature: MAX HOT Engine coolant temperature: Below 65°C (149°F) Ambient temperature: Below 10°C (50°F) Light control switch: OFF Blower switch OFF → LO ALT (E41-25) - Body ground(*1) B - Body ground Generator signal Engine idling Pulse generation HLS (E41-27) - Body ground(*1) BR - Body ground Headlight signal Engine idling Below 1 V Light control switch: ON LIN1 (E41-37) - GND (E41-14) B - W-B LIN communication signal Ignition switch on (IG) Pulse generation LOCK (E41-8) - SG-2 (E41-13)(*2) W - G Compressor lock sensor signal Ignition switch on (IG)
AUTO switch ON
A/C switch ON
Magnetic clutch ONPulse generation
(see waveform 5)MGC (E41-20) - GND (E41-14)(*2) V - W-B Magnetic clutch relay signal Ignition switch on (IG)
Magnetic clutch OFF10 to 14 V MGC (E41-20) - GND (E41-14)(*2) V - W-B Magnetic clutch relay signal Ignition switch on (IG)
Magnetic clutch ONBelow 1.5 V BUB G (c1-2) - Body ground - Ground for BUS IC Always Below 1 V BUS (c1-3) - BUB G (c1-2) - BUS IC control signal Ignition switch on (IG) Pulse generation B BUS (c1-4) - BUB G (c1-2) - Power supply for BUS IC Ignition switch on (IG) 11 to 13 V SGA (c1-5) - Body ground - Ground for evaporator temperature sensor Always Below 1 V TEA (c1-6) - SGA (c1-5) - Evaporator temperature sensor signal Ignition switch on (IG) 1.4 to 1.8 V Evaporator temperature: 15°C (59°F) - HINT:
- *1: w/ PTC heater
- *2: for 2GR-FE
Using an oscilloscope, measure the waveform 1.
Compressor and pulley operation signal Item Content Symbols (Terminal No.) SOL+ (E41-2) - GND (E41-14) Tool Setting 5 V/DIV., 500 μsec./DIV. Condition Engine idling, Blower switch LO, A/C switch ON Using an oscilloscope, measure the waveform 2.
Blower motor control signal Item Content Symbols (Terminal No.) BLW (E41-23) - GND (E41-14) Tool Setting 1 V/DIV., 500 μsec./DIV. Condition Ignition switch on (IG), Blower switch LO - HINT:
- When the blower level is increased, the duty ratio changes accordingly.
Using an oscilloscope, measure the waveform 3.
CAN communication signal Item Content Symbols (Terminal No.) CANH (E41-11) - GND (E41-14) Tool Setting 1 V/DIV., 10 μsec./DIV. Condition Ignition switch on (IG) - HINT:
- The waveform varies depending on the CAN communication signal.
Using an oscilloscope, measure the waveform 4.
CAN communication signal Item Content Symbols (Terminal No.) CANL (E41-12) - GND (E41-14) Tool Setting 1 V/DIV., 10 μsec./DIV. Condition Ignition switch on (IG) - HINT:
- The waveform varies depending on the CAN communication signal.
Using an oscilloscope, measure the waveform 5.
Compressor lock sensor signal Item Content Symbols (Terminal No.) LOCK (E41-8) - SG-2 (E41-13) Tool Setting 500 mV/DIV., 20 msec./DIV. Condition Ignition switch on (IG), AUTO switch ON, A/C switch ON, Magnetic clutch ON
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CHECK AIR CONDITIONING CONTROL |

Measure the voltage and resistance of the connectors.
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition IG+ (E26-2) - GND (E26-7) L - W-B Power source (IG) Ignition switch on (IG) 10 to 14 V GND (E26-7) - Body ground W-B - Body Ground Ground for air conditioning control assembly Always Below 1 V LIN1 (E26-11) - GND (E26-7) B - W-B LIN communication signal Ignition switch on (IG) Pulse generation +B (E26-1) - GND (E26-7) R - W-B Power source (Back-up) Always 10 to 14 V ACC (E26-8) - GND (E26-7) GR - W-B ACC power supply Ignition switch on (ACC) 10 to 14 V