TERMINALS OF ECU
CHECK SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)
(a) Disconnect the U2 sliding roof ECU (sliding roof drive gear sub-assembly) connector.
(b) Measure the resistance and voltage according to the value(s) in the table below.
HINT:
Measure the values on the wire harness side with the connector disconnected.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| U2-1 (B) - U2-2 (E) | P - W-B | Battery power supply | Always | 11 to 14 V |
| U2-6 (IG) - U2-2 (E) | B - W-B | IG power supply | Engine switch off | Below 1 V |
| U2-6 (IG) - U2-2 (E) | B - W-B | IG power supply | Engine switch on (IG) | 11 to 14 V |
| U2-2 (E) - Body ground | W-B - Body ground | Ground | Always | Below 1 Ω |
If the result is not as specified, there may be a malfunction in the wire harness.
(c) Reconnect the U2 sliding roof ECU (sliding roof drive gear sub-assembly) connector.
(d) Measure the voltage according to the value(s) in the table below.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| U2-10 (OPN) - U2-2 (E) | L - W-B | Sliding roof motor open | Engine switch on (IG), OPEN switch on | Below 1 V |
| U2-10 (OPN) - U2-2 (E) | L - W-B | Sliding roof motor open | Engine switch on (IG), OPEN switch off | 11 to 14 V |
| U2-9 (CLS) - U2-2 (E) | R - W-B | Sliding roof motor close | Engine switch on (IG), CLOSE switch on | Below 1 V |
| U2-9 (CLS) - U2-2 (E) | R - W-B | Sliding roof motor close | Engine switch on (IG), CLOSE switch off | 11 to 14 V |
| U2-5 (OPN) - U2-2 (E) | W - W-B | Sliding roof motor up | Engine switch on (IG), UP switch on | Below 1 V |
| U2-5 (OPN) - U2-2 (E) | W - W-B | Sliding roof motor up | Engine switch on (IG), UP switch off | 11 to 14 V |
| U2-9 (CLS) - U2-2 (E) | R - W-B | Sliding roof motor down | Engine switch on (IG), DOWN switch on | Below 1 V |
| U2-9 (CLS) - U2-2 (E) | R - W-B | Sliding roof motor down | Engine switch on (IG), DOWN switch off | 11 to 14 V |
If the result is not as specified, the sliding roof ECU (sliding roof drive gear sub-assembly) may be malfunctioning.
CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)
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Problem Symptoms Table
Diagnosis SystemLexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Lighting System: ACC Signal Circuit
DESCRIPTION This circuit detects the engine switch on (ACC) or off condition, and sends it to the main body ECU (multiplex network body ECU). WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
Before r ...
Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Lighting System: IG Signal Circuit
DESCRIPTION This circuit detects the engine switch on (IG) or off condition, and sends it to the main body ECU (multiplex network body ECU). WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE:
Inspect the fuses for circuits related to this system before performing the following procedure.
Before re ...