Lexus IS250 IS220d GSE20 ALE20 - DOOR LOCK
ENTRY AND START SYSTEM - TERMINALS OF ECU
CHECK CERTIFICATION ECU |
Disconnect the P33 ECU connector.
Measure the voltage and resistance according to the value(s) in the table below.
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
+B1 (P33-1) - Body ground | L - Body ground | +B power supply | Always | 10 to 14 V |
IG (P33-18) - Body ground | B - Body ground | Ignition power supply | Engine switch off | Below 1 V |
IG (P33-18) - Body ground | B - Body ground | Ignition power supply | Engine switch on (IG) | 10 to 14 V |
E (P33-17) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
ACC (P33-19) - Body ground | O - Body ground | ACC power supply | Engine switch off | Below 1 V |
ACC (P33-19) - Body ground | O - Body ground | ACC power supply | Engine switch on (ACC) | 10 to 14 V |
TSW1 (P33-3) - Body ground | Y - Body ground | Entry lock switch signal | Front lock switch LH not pushed | 10 KΩ or higher |
TSW1 (P33-3) - Body ground | Y - Body ground | Entry lock switch signal | Front lock switch LH pushed | Below 1 Ω |
TSW2 (P33-4) - Body ground | BR - Body ground | Entry lock switch signal | Front lock switch RH not pushed | 10 KΩ or higher |
TSW2 (P33-4) - Body ground | BR - Body ground | Entry lock switch signal | Front lock switch RH pushed | Below 1 Ω |
LIN (P33-10) - Body ground | V - Body ground | LIN line | Always | 10 kΩ or higher |
MPX1 (P33-27) - Body ground | GR - Body ground | MPX line | Always | 10 kΩ or higher |
MPX2 (P33-28) - Body ground | GR - Body ground | MPX line | Always | 10 kΩ or higher |
AGND (P33-40) - Body ground | LG - Body ground | Ground | Always | Below 1 Ω |
If the result is not as specified, the wire harness side may have a malfunction.
Reconnect the P33 ECU connector.
Measure the voltage according to the value(s) in the table below.
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
CLG1 (P33-33) - CG1B (P33-34) | R - BR | Door electrical key oscillator (front LH) sensor signal | All doors closed, all doors locked and engine switch off | Alternating between 5 V and below 1 V |
CLG1 (P33-33) - CG1B (P33-34) | R - BR | Door electrical key oscillator (front LH) sensor signal | Door unlocked or door open | Below 1 V |
SEN1 (P33-22) - E (P33-17) | W (*1) - W-B G (*2) - W-B | Touch sensor detection signal | Outside door handle touched | Below 1 V |
SEN1 (P33-22) - E (P33-17) | W (*1) - W-B G (*2) - W-B | Touch sensor detection signal | Outside door handle not touched | 10 to 14 V |
SEL1 (P33-5) - E (P33-17) | W (*1) - W-B B (*2) - W-B | Touch sensor activation control signal | Move the key more than 5 m (16.4 ft) away from the front door LH | 10 to 14 V |
SEL1 (P33-5) - E (P33-17) | W (*1) - W-B B (*2) - W-B | Touch sensor activation control signal | Bring it to the outside handle | Below 1 V |
CLG2 (P33-35) - CG2B (P33-36) | G - BR | Door electrical key oscillator (front RH) sensor signal | All doors closed, all doors locked and engine switch off | Alternating between 5 V and below 1 V |
CLG2 (P33-35) - CG2B (P33-36) | G - BR | Door electrical key oscillator (front RH) sensor signal | Door unlocked or door open | Below 1 V |
SEN2 (P33-23) - E (P33-17) | W (*1) - W-B G (*2) - W-B | Touch sensor detection signal | Outside door handle touched | Below 1 V |
SEN2 (P33-23) - E (P33-17) | W (*1) - W-B G (*2) - W-B | Touch sensor detection signal | Outside door handle not touched | 10 to 14 V |
SEL2 (P33-6) - E (P33-17) | W (*1) - W-B B (*2) - W-B | Touch sensor activation control signal | Move the key more than 5 m (16.4 ft) away from the front door RH | 10 to 14 V |
SEL2 (P33-6) - E (P33-17) | W (*1) - W-B B (*2) - W-B | Touch sensor activation control signal | Bring it to the outside handle | Below 1 V |
CLG5 (P33-11) - CG5B (P33-12) | Y - V | Indoor electrical key oscillator (front) sensor signal | 30 seconds after driver side door opened and closed, engine switch off | Alternating between 5 V and below 1 V |
CLG5 (P33-11) - CG5B (P33-12) | Y - V | Indoor electrical key oscillator (front) sensor signal | Within 30 seconds driver side door opened and closed, engine switch off | Below 1 V |
CLG6 (P33-13) - CG6B (P33-14) | LG - O | Indoor electrical key oscillator (rear) sensor signal | 30 seconds after driver side door opened and closed, engine switch off | Alternating between 5 V and below 1 V |
CLG6 (P33-13) - CG6B (P33-14) | LG - O | Indoor electrical key oscillator (rear) sensor signal | Within 30 seconds driver side door opened and closed, engine switch off | Below 1 V |
CLG7 (P33-15) - CG7B (P33-16) | SB - P | Luggage electrical key oscillator (inner) sensor signal | Luggage compartment door opening switch OFF | Alternating between 5 V and below 1 V |
CLG7 (P33-15) - CG7B (P33-16) | SB - P | Luggage electrical key oscillator (inner) sensor signal | Luggage compartment door opening switch ON | Below 1 V |
CLG8 (P33-31) - CG8B (P33-32) | B - W | Luggage electrical key oscillator (outer) sensor signal | Luggage compartment door opening switch OFF | Alternating between 5 V and below 1 V |
CLG8 (P33-31) - CG8B (P33-32) | B - W | Luggage electrical key oscillator (outer) sensor signal | Luggage compartment door opening switch ON | Below 1 V |
RCO (P33-29) - E (P33-17) | LG - W-B | Entry door control receiver power source | Engine switch off, all doors closed and electrical key switch on. | 4.6 to 5.4 V |
RCO (P33-29) - E (P33-17) | LG - W-B | Entry door control receiver power source | Engine switch off, all doors closed and electrical key switch off. | Below 1 V |
RSSI (P33-39) - E (P33-17) | Y - W-B | Entry door control receiver electric wave existence signal | Engine switch off, all doors closed, the electrical key is not in the action area. | 10 to 14 V |
RSSI (P33-39) - E (P33-17) | Y - W-B | Entry door control receiver electric wave existence signal | Engine switch off, all doors closed, the electrical key is in the action area. | Below 1 V |
RDA (P33-38) - E (P33-17) | R - W-B | Entry door control receiver data input signal | Engine switch off, all doors closed and electrical key switch off. | 10 to 14 V |
RDA (P33-38) - E (P33-17) | R - W-B | Entry door control receiver data input signal | Engine switch off, all doors closed and electrical key switch on. | Pulse generation |
RDA (P33-38) - Body ground | R - Body ground | Tuner input signal | Engine switch off, all doors closed, the electrical key is not in the action area. | 10 to 14 V |
RDA (P33-38) - Body ground | R - Body ground | Tuner input signal | The electrical key is in the action area. | Pulse generation |
ASEL (P33-37) - Body ground | SB - Body ground | Tuner select signal | Engine switch off, luggage compartment door closed. | 4.6 to 5.4 V |
ASEL (P33-37) - Body ground | SB - Body ground | Tuner select signal | Engine switch off, luggage compartment door open. | Below 1 V |
VC5 (P33-30) - Body ground | L - Body ground | Transponder key amplifier power supply | Electrical key is not in the vehicle. | Below 1 V |
VC5 (P33-30) - Body ground | L - Body ground | Transponder key amplifier power supply | Have the electrical key outside the cabin and open the driver's door. | 4.6 to 5.4 V |
TXCT (P33-8) - Body ground | G - Body ground | Transponder key amplifier output signal | Electrical key is not in the cabin. | Below 1 V |
TXCT (P33-8) - Body ground | G - Body ground | Transponder key amplifier output signal | Have the electrical key outside the cabin and open the driver's door. | Pulse generation (see waveform 1) |
CODE (P33-9) - Body ground | GR - Body ground | Transponder key amplifier communication signal | Electrical key is not in the cabin. | Below 1 V |
CODE (P33-9) - Body ground | GR - Body ground | Transponder key amplifier communication signal | Have the electrical key outside the cabin and open the driver's door. | Pulse generation (see waveform 2) |
*1: LHD Models
*2: RHD Models
If the result is not as specified, the ECU may have a malfunction.

Inspect using an oscilloscope.
Terminal | TXCT - Body ground |
Tool Setting | 2 V/DIV, 10 ms/DIV |
Condition | The electrical key is not in the cabin. |

Inspect using an oscilloscope.
Terminal | CODE - Body ground |
Tool Setting | 2 V/DIV, 20 ms/DIV |
Condition | The electrical key is not in the cabin. |
MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH) |
Measure the voltage according to the value(s) in the table below.
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
LPSW (Q3-13) - Body ground | BR - Body ground | Luggage compartment opener switch signal | Luggage compartment opener switch OFF | 10 to 14 V |
LPSW (Q3-13) - Body ground | BR - Body ground | Luggage compartment opener switch signal | Luggage compartment opener switch ON | Below 1 V |
If the result is not as specified, the junction block may have a malfunction.