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.
Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition E41-2 (SOL+) - E41-14 (GND) GR - W-B A/C compressor operation signal - Engine idling
- Refrigerant pressure: Normal
- Blower switch LO
- A/C switch ON
Pulse generation
(see waveform 1)E41-9 (PRE) - E41-13 (SG-2) L - G Air conditioning pressure sensor signal Refrigerant pressure: Normal 0. 76 to 4. 73 V E41-9 (PRE) - E41-13 (SG-2) 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 E41-9 (PRE) - E41-13 (SG-2) 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 E41-23 (BLW) - E41-14 (GND) R - W-B Blower motor control signal - Ignition switch on (IG)
- Blower switch LO
Pulse generation
(see waveform 2)E41-33 (TSD) - E41-31 (S5-4) L - LG Driver side solar sensor signal - Ignition switch on (IG)
- Solar sensor subject to electric light
0.8 to 4.3 V E41-32 (TSP) - E41-31 (S5-4) P - LG Passenger side solar sensor signal - Ignition switch on (IG)
- Solar sensor subject to electric light
0.8 to 4.3 V E41-29 (TR) - E41-34 (SG-1) GR - V Room temperature sensor signal - Ignition switch on (IG)
- Vehicle interior temperature: 25°C (77°F)
1.8 to 2.2 V E41-34 (SG-1) - Body ground V - Body ground Ground for room temperature sensor Always Below 1 Ω E41-14 (GND) - Body ground W-B - Body ground Ground for main power supply Always Below 1 Ω E41-1 (IG+) - E41-14 (GND) Y - W-B Power source (IG) Ignition switch on (IG) 11 to 14 V E41-21 (B) - E41-14 (GND) R - W-B Power source (Back-up) Always 11 to 14 V E41-10 (S5-3) - E41-14 (GND) B - W-B Power supply for pressure sensor Ignition switch on (IG) 4.5 to 5.5 V E41-11 (CANH) - E41-14 (GND) V - W-B Hi-level CAN bus line Ignition switch on (IG) Pulse generation
(see waveform 3)E41-12 (CANL) - E41-14 (GND) W - W-B Lo-level CAN bus line Ignition switch on (IG) Pulse generation
(see waveform 4)E41-38 (RDEF) - E41-14 (GND) B - W-B Rear defogger switch signal - Ignition switch on (IG)
- Rear defogger switch OFF
11 to 14 V E41-38 (RDEF) - E41-14 (GND) B - W-B Rear defogger switch signal - Ignition switch on (IG)
- Rear defogger switch ON
Below 1 V E41-13 (SG-2) - Body ground G - Body ground Ground for pressure sensor Always Below 1 Ω E41-3 (PTC1) - Body ground*1 W - Body ground PTC NO. 1 heater relay operation signal - Engine idling
- 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 LO
11 to 14 V E41-3 (PTC1) - Body ground*1 W - Body ground PTC NO. 1 heater relay operation signal - Engine idling
- 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
Below 1 V E41-22 (PTC2) - Body ground*1 B - Body ground PTC NO. 2 heater relay operation signal - Engine idling
- 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 LO
11 to 14 V E41-22 (PTC2) - Body ground*1 B - Body ground PTC NO. 2 heater relay operation signal - Engine idling
- 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
Below 1 V E41-4 (PTC3) - Body ground*1 R - Body ground PTC NO. 3 heater relay operation signal - Engine idling
- 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 LO
11 to 14 V E41-4 (PTC3) - Body ground*1 R - Body ground PTC NO. 3 heater relay operation signal - Engine idling
- 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
Below 1 V E41-25 (ALT) - Body ground*1 B - Body ground Generator signal Engine idling Pulse generation E41-27 (HLS) - Body ground*1 BR - Body ground Headlight signal - Engine idling
- Light control switch ON
Below 1 V E41-27 (HLS) - Body ground*1 BR - Body ground Headlight signal - Engine idling
- Light control switch OFF
11 to 14 V E41-37 (LIN1) - E41-14 (GND) B - W-B LIN communication signal Ignition switch on (IG) Pulse generation E41-8 (LOCK) - E41-13 (SG-2)*2 W - G Compressor lock sensor signal - Engine idling
- A/C switch ON (Magnetic clutch operating)
- Blower switch LO
Pulse generation
(see waveform 5)E41-20 (MGC) - E41-14 (GND)*2 V - W-B Magnetic clutch relay signal - Engine idling
- A/C switch OFF
- Blower switch LO
11 to 14 V E41-20 (MGC) - E41-14 (GND)*2 V - W-B Magnetic clutch relay signal - Engine idling
- A/C switch ON (Magnetic clutch operating)
- Blower switch LO
Below 1.5 V c1-2 (BUS G) - Body ground - Ground for BUS IC Always Below 1 Ω c1-3 (BUS) - c1-2 (BUS G) - BUS IC control signal Ignition switch on (IG) Pulse generation c1-4 (B BUS) - c1-2 (BUS G) - Power supply for BUS IC Ignition switch on (IG) 11 to 14 V c1-5 (SGA) - Body ground - Ground for evaporator temperature sensor Always Below 1 Ω c1-6 (TEA) - c1-5 (SGA) - Evaporator temperature sensor signal - Ignition switch on (IG)
- Evaporator temperature: 15°C (59°F)
1.4 to 1.8 V - HINT:
- *1: w/ PTC heater
- *2: for 2GR-FE
Using an oscilloscope, measure the waveform 1.
Compressor and pulley operation signal Item Content Terminal No. (Symbol) E41-2 (SOL+) - E41-14 (GND) Tool Setting 5 V/DIV., 500 μsec./DIV. Condition Engine idling, Blower switch LO, A/C switch ON, Refrigerant pressure: Normal Using an oscilloscope, measure the waveform 2.
Blower motor control signal Item Content Terminal No. (Symbol) E41-23 (BLW) - E41-14 (GND) 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 Terminal No. (Symbol) E41-11 (CANH) - E41-14 (GND) 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 Terminal No. (Symbol) E41-12 (CANL) - E41-14 (GND) 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 Terminal No. (Symbol) E41-8 (LOCK) - E41-13 (SG-2) Tool Setting 500 mV/DIV., 20 msec./DIV. Condition Engine idling, A/C switch ON (Magnetic clutch operating), Blower switch LO
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CHECK AIR CONDITIONING CONTROL |

Measure the voltage and resistance of the connectors.
Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition E109-2 (IG+) - E109-8 (GND) L - W-B Power source (IG) Ignition switch on (IG) 11 to 14 V E109-8 (GND) - Body ground W-B - Body Ground Ground for air conditioning control assembly Always Below 1 Ω E109-12 (LIN1) - E109-8 (GND) B - W-B LIN communication signal Ignition switch on (IG) Pulse generation E109-1 (+B) - E109-8 (GND) R - W-B Power source (Back-up) Always 11 to 14 V E109-9 (ACC) - E109-8 (GND) GR - W-B ACC power supply Ignition switch on (ACC) 11 to 14 V