ON-VEHICLE INSPECTION
PROCEDURE
1. INSPECT SEMICONDUCTOR POWER INTEGRATION ECU (SIGNAL READING CHECK)
NOTICE:
Both present and history signal readings will be cleared if the semiconductor power integration ECU is removed. Make sure not to remove it before inspection.
HINT:
The signal readings of the semiconductor power integration ECU can be checked by inspecting the voltage at the diagnosis terminal.
(a) Signal reading check
(1) Turn the engine switch on (IG).
| (2) Connect the positive (+) terminal of a voltmeter to the semiconductor power integration ECU and the negative (-) terminal to the body ground. |
|
(3) Using the illustration below as a reference, determine whether any channels are malfunctioning based on the observed signal reading.
HINT:
| Channel | Connected Electrical Load |
|---|---|
| ch0 | Cooler compressor assembly (Magnetic clutch assembly) |
| ch1 | Rear window defogger wire |
| ch2 | Windshield deicer wire*1 |
| ch3 | Front fog lights |
| ch4 | Daytime running lights*2 |
| ch5 | Stop lights |
| ch6 | High beam headlight RH*2 |
| ch7 | High beam headlight LH*2 |
2. INSPECT SEMICONDUCTOR POWER INTEGRATION ECU (RESULTS OF SIGNAL READING CHECK)
(a) Results of signal reading check
(1) Depending on the signal reading, perform troubleshooting according to the table below.
| Output Signal Reading | Repair Method |
|---|---|
| Normal | Continue troubleshooting for each system. |
| The unit is malfunctioning | Replace the semiconductor power integration ECU. |
| A malfunction in a channel (ch0 to ch7) |
|
HINT:
Make sure to clear the signal readings by disconnecting the cable from the negative (-) battery terminal after replacement or repair of the malfunctioning part.
(2) If no signal readings are output, perform troubleshooting according to the following troubleshooting procedure.
| *a | Component without semiconductor power integration ECU (No. 1 Engine Room Relay Block) | - | - |
Click here
Standard Voltage:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 1D-11 - Body ground | Engine switch on (IG) | 11 to 14 V |
If the result is not as specified, repair or replace the wire harness or connector.
Components
RemovalLexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Can Communication System: Open in Bus 4 Main Bus Line
DESCRIPTION There may be an open circuit in one of the bus 4 main lines when the resistance between terminals 22 (CA2H) and 7 (CA2L) of the network gateway ECU is 70 Ω or higher. Symptom Trouble Area Resistance between terminals 22 (CA2H) and 7 (CA2L) of network gateway ECU is 70 Ω or hig ...
Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Steering Lock System: Precaution
PRECAUTION PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE BATTERY TERMINAL NOTICE: When disconnecting the cable from the negative (-) battery terminal, initialize the following system(s) after the cable is reconnected: System See Procedure Lane Control System Pre-collision System ...