Lexus IS250 IS220d GSE20 ALE20 - AIR CONDITIONING
AIR CONDITIONING SYSTEM - TERMINALS OF ECU
AIR CONDITIONING AMPLIFIER |
*1: Except 2AD-FHV
*2: For 2AD-FHV
- HINT:
- Check from the rear of the connector while it is connected to the A/C amplifier.
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
J58-1 (B) - J58-20 (GND) | Y - W-B | Power source (Back-up) | Always | 10 to 14 V |
J58-2 (MHTR) - J58-20 (GND) | BR - W-B | MIR/HTR relay signal | Engine switch on (IG), REAR DEF switch: OFF | 10 to 14 V |
J58-2 (MHTR) - J58-20 (GND) | BR - W-B | MIR/HTR relay signal | Engine switch on (IG), REAR DEF switch: ON | Below 1 V |
J58-3 (RDEF) - J58-20 (GND) | B - W-B | DEFOG relay signal | Engine switch on (IG), FRONT DEF switch: OFF | 10 to 14 V |
J58-3 (RDEF) - J58-20 (GND) | B - W-B | DEFOG relay signal | Engine switch on (IG), FRONT DEF switch: ON | Below 1 V |
*1 J58-4 (HTR2) - J58-20 (GND) | LG - W-B | GLW RLY2 relay signal | Engine switch on (IG) | 10 to 14 V |
*1 J58-4 (HTR2) - J58-20 (GND) | LG - W-B | GLW RLY2 relay signal | Engine switch on (IG) Engine running at 850 rpm or more, Ambient temperature 0°C (32°F) or less, Engine coolant temperature 69°C (156°F) or less, Temperature switch: MAX HOT, Blower switch: LO | Below 1 V |
J58-5 (SOL+) - J58-20 (GND) | G - W-B | A/C compressor operation signal | Engine switch on (IG), A/C switch: ON | Pulse generation (See waveform 1) |
J58-11 (BLW) - J58-20 (GND) | O - W-B | Blower motor speed control signal | Engine switch on (IG), Blower switch: ON | Pulse generation (See waveform 2) |
J58-13 (PRE) - J58-38 (SG-2) | V - P | Pressure sensor signal | Start engine, Operate A/C system, Refrigerant pressure: Abnormal pressure (more than 3,030 kPa (31.0 kgf/cm, 440 psi)) | 4.7 V or higher |
J58-13 (PRE) - J58-38 (SG-2) | V - P | Pressure sensor signal | Start engine, Operate A/C system, Refrigerant pressure: Abnormal pressure (less than 180 kPa (1.9 kgf/cm, 27 psi)) | Below 0.7 V |
J58-13 (PRE) - J58-38 (SG-2) | V - P | Pressure sensor signal | Start engine, Operate A/C system, Refrigerant pressure: Abnormal pressure (more than 3,030 kPa (31.0 kgf/cm, 440 psi) and less than 180 kPa (1.9 kgf/cm, 27 psi)) | 0.7 to 4.7 V |
J58-14 (TSP) - J58-20 (GND) | P - W-B | Passenger side solar sensor signal | Engine switch on (IG), Solar sensor subjected to electric light | 0.8 to 4.3 V |
J58-14 (TSP) - J58-20 (GND) | P - W-B | Passenger side solar sensor signal | Engine switch on (IG), Solar sensor is covered with a cloth | Below 0.8 V |
J58-16 (TR) - J58-19 (SG-1) | G - L | Room temperature sensor signal | Engine switch on (IG), Cabin temperature: 25°C (77°F) | 1.6 to 1.8 V |
J58-16 (TR) - J58-19 (SG-1) | G - L | Room temperature sensor signal | Engine switch on (IG), Cabin temperature: 40°C (104°F) | 0.8 to 1.0 V |
J58-19 (SG-1) - Body ground | L - Body ground | Ground for room temperature sensor | Always | Below 1 V |
J58-20 (GND) - Body ground | W-B - Body ground | Ground for main power supply | Always | Below 1 V |
J58-21 (IG+) - J58-20 (GND) | B - W-B | Power source (IG) | Engine switch on (IG) | 10 to 14 V |
J58-21 (IG+) - J58-20 (GND) | B - W-B | Power source (IG) | Engine switch off | Below 1 V |
*1 J58-23 (HTR1) - J58-20 (GND) | L - W-B | GLW RLY1 relay signal | Engine switch on (IG) | 10 to 14 V |
*1 J58-23 (HTR1) - J58-20 (GND) | L - W-B | GLW RLY1 relay signal | Engine switch on (IG) Engine running at 850 rpm or more, Ambient temperature 0°C (32°F) or less, Engine coolant temperature 69°C (156°F) or less, Temperature switch: MAX HOT, blower switch: LO | Below 1 V |
J58-26 (S5-2) - J58-38 (SG-2) | W - P | Power supply for pressure sensor | Engine switch on (IG), A/C switch: ON | 4.5 to 5.5 V |
J58-26 (S5-2) - J58-38 (SG-2) | W - P | Power supply for pressure sensor | Engine switch on (IG), A/C switch: OFF | Below 1 V |
J58-30 (MPX+) - J58-31 (MPX-) | BR - BR | Multiplex communication system | Multiplex communication circuit | - |
*1 J58-33 (DGS1) - J58-39 (SG-6) | R - Y | Exhaust gas sensor signal (Nox) | 30 seconds have elapsed after the engine switch is turned on (IG) and sensor is exposed to exhaust gas | 1.0 to 4.5 V |
*1 J58-34 (DGS) - J58-39 (SG-6) | BR - Y | Exhaust gas sensor signal (HC, CO) | 30 seconds have elapsed after the engine switch is turned on (IG) and sensor is exposed to exhaust gas | 1.0 to 4.5 V |
J58-35 (TSD) - J58-20 (GND) | LG - W-B | Driver side solar sensor signal | Engine switch on (IG), Solar sensor subjected to electric light | 0.8 to 4.3 V |
J58-35 (TSD) - J58-20 (GND) | LG - W-B | Driver side solar sensor signal | Engine switch on (IG), Solar sensor is covered with a cloth | Below 0.8 V |
*2 J58-36 (TAM) - J58-37 (SG) | SB - L | Ambient temperature sensor signal | Engine switch on (IG) at 25°C (77°F) | 1.8 to 2.2 V |
*2 J58-36 (TAM) - J58-37 (SG) | SB - L | Ambient temperature sensor signal | Engine switch on (IG) at 40°C (104°F) | 1.2 to 1.6 V |
*2 J58-37 (SG) - Body ground | L - Body ground | Ground for ambient temperature sensor | Always | Below 1 V |
J58-38 (SG-2) - Body ground | P - Body ground | Ground for pressure sensor | Always | Below 1 V |
J58-39 (SG-6) - Body ground | Y - Body ground | Ground for exhaust gas sensor | Always | Below 1 V |
e1- 2 (BUS G) - Body ground | - | Ground for BUS IC | Always | Below 1 V |
e1- 3 (BUS) - e1-2 (BUS G) | - | BUS IC control signal | Engine switch off → on (IG) | Pulse generation |
e1-4 (B BUS) - e1-2 (BUS G) | - | Power supply for BUS IC | Engine switch on (IG) | 10 to 14 V |
e1-4 (B BUS) - e1-2 (BUS G) | - | Power supply for BUS IC | Engine switch off | Below 1 V |
e1-6 (TE) - e1-5 (SG) | - | Evaporator temperature sensor signal | Engine switch on (IG), Evaporator temperature 0°C (32°F) | 2.0 to 2.4 V |
e1-6 (TE) - e1-5 (SG) | - | Evaporator temperature sensor signal | Engine switch on (IG), Evaporator temperature 15°C (59°F) | 1.4 to 1.8 V |

Waveform 1:
Item | Contents |
Terminal No. (Symbols) | J58-5 (SOL+) - J58-20 (GND) |
Tool Setting | 5 V/DIV., 500 μs/DIV. |
Vehicle Condition | Engine switch on (IG) A/C switch: ON |

Waveform 2:
Item | Contents |
Terminal No. (Symbols) | J58-11 (BLW) - J58-20 (GND) |
Tool Setting | 1 V/DIV., 500 μs/DIV. |
Vehicle Condition | Engine switch on (IG) Blower switch: ON |
MULTI-DISPLAY (w/ NAVIGATION SYSTEM) |
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
J54-3 (GND1) - Body ground | W-B - Body ground | Ground for heater control panel | Always | Below 1 V |
J54-10 (IG) - J54-3 (GND1) | B - W-B | Power source (IG) | Engine switch on (IG) | 10 to 14 V |
J54-10 (IG) - J54-3 (GND1) | B - W-B | Power source (IG) | Engine switch off | Below 1 V |
J54-11 (ACC) - J54-3 (GND1) | O - W-B | Power source (ACC) | Engine switch on (ACC) | 10 to 14 V |
J54-11 (ACC) - J54-3 (GND1) | O - W-B | Power source (ACC) | Engine switch off | Below 1 V |
J54-12 (+B1) - J54-3 (GND1) | LG - W-B | Power source (Back-up) | Always | 10 to 14 V |
INTEGRATION CONTROL & PANEL ASSEMBLY (w/o NAVIGATION SYSTEM) |
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
J53-4 (IG+) - J53-8 (E) | B - W-B | Power source (IG) | Engine switch on (IG) | 10 to 14 V |
J53-4 (IG+) - J53-8 (E) | B - W-B | Power source (IG) | Engine switch off | Below 1 V |
J53-5 (ACC) - J53-8 (E) | O - W-B | Power source (ACC) | Engine switch on (ACC) | 10 to 14 V |
J53-5 (ACC) - J53-8 (E) | O - W-B | Power source (ACC) | Engine switch off | Below 1 V |
J53-8 (E) - Body ground | W-B - Body ground | Ground for heater control panel | Always | Below 1 V |
J53-14 (B) - J53-8 (E) | LG - W-B | Power source (Back-up) | Always | 10 to 14 V |
ECM (for 4GR-FSE) |
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
E3-10 (LCKI) - E4-7 (E1) | B - BR | Compressor lock sensor signal | Engine idling, Blower switch: LO, A/C switch: ON | Pulse generation (See waveform 3) |
E4-7 (E1) - Body ground | BR - Body ground | Ground for ECM | Always | Below 1 V |
E5-30 (E3) - Body ground | BR - Body ground | Ground for ambient temperature sensor | Always | Below 1 V |
A6-13 (ACMG) - E4-7 (E1) | L - BR | Compressor operation signal | Engine idling, Blower switch: LO, A/C switch: OFF | 10 to 14 V |
A6-13 (ACMG) - E4-7 (E1) | L - BR | Compressor operation signal | Engine idling, Blower switch: LO, A/C switch: ON | Below 1 V |
A5-18 (TAM) - E5-30 (E3) | V-R - BR | Ambient temperature sensor signal | Engine switch on (IG) at 25°C (77°F) | 1.8 to 2.2 V |
A5-18 (TAM) - E5-30 (E3) | V-R - BR | Ambient temperature sensor signal | Engine switch on (IG) at 40°C (104°F) | 1.2 to 1.6 V |

Waveform 3:
Item | Contents |
Terminal No. (Symbols) | E3-10 (LCKI) - E4-7 (E1) |
Tool Setting | 200 mV/DIV., 10 ms/DIV. |
Vehicle Condition | Engine switch on (IG) Blower switch: LO A/C switch: ON |