Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Power Source Circuit

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Vehicle Interior / Seat / Rear Power Seat Control System(for Second Row) / Power Source Circuit

DESCRIPTION

Power is supplied to the fold seat control ECU through the ECU-DCC NO. 2, P/SEAT R/R*1, P/SEAT R/L*2 and ECU-IG1 NO. 4 fuses.

  • *1: for Rear Right Seat
  • *2: for Rear Left Seat

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (FOLD SEAT CONTROL ECU - BATTERY AND BODY GROUND)

*A

for Rear RH Seat

*B

for Rear LH Seat

*a

Front view of wire harness connector (to Fold Seat Control ECU)

(a) Disconnect the x3*1 or y3*2 and x4*1 or y4*2 fold seat control ECU (rear right seat) connectors.

  • *1: for Rear RH Seat
  • *2: for Rear LH Seat

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

for Rear RH Seat

Tester Connection

Condition

Specified Condition

x4-1 (IND1) - Body ground

Always

11 to 14 V

x4-2 (+B) - Body ground

Always

11 to 14 V

x3-1 (ECUB) - Body ground

Always

11 to 14 V

x3-3 (IG) - Body ground

Engine switch off → on (IG)

Below 1 V → 11 to 14 V
for Rear LH Seat

Tester Connection

Condition

Specified Condition

y4-1 (IND1) - Body ground

Always

11 to 14 V

y4-2 (+B) - Body ground

Always

11 to 14 V

y3-1 (ECUB) - Body ground

Always

11 to 14 V

y3-3 (IG) - Body ground

Engine switch off → on (IG)

Below 1 V → 11 to 14 V

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

for Rear RH Seat

Tester Connection

Condition

Specified Condition

x4-10 (GND) - Body ground

Always

Below 1 Ω

x4-9 (GND2) - Body ground

Always

Below 1 Ω

x3-40 (IND2) - Body ground

Always

Below 1 Ω
for Rear LH Seat

Tester Connection

Condition

Specified Condition

y4-10 (GND) - Body ground

Always

Below 1 Ω

y4-9 (GND2) - Body ground

Always

Below 1 Ω

y3-40 (IND2) - Body ground

Always

Below 1 Ω
OK

GO TO PROBLEM SYMPTOMS TABLE

NG

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    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual

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