Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Terminals Of Ecu

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Vehicle Interior / Door Lock / Power Door Lock Control System / Terminals Of Ecu

TERMINALS OF ECU

CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

(a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

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(b) Reconnect the instrument panel junction block assembly connector.

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

Tester Connection

Wiring Color

Terminal Description

Condition

Specified Condition

MB-11 (GND1) - Body ground

-

Ground

Always

Below 1 Ω

MB-30 (ACC) - Body ground

-

ACC power supply

Engine switch on (ACC)

11 to 14 V

MB-30 (ACC) - Body ground

-

ACC power supply

Engine switch off

Below 1 V

MB-31 (BECU) - Body ground

-

Battery power supply

Always

11 to 14 V

MB-32 (IG) - Body ground

-

IG power supply

Engine switch on (IG)

11 to 14 V

MB-32 (IG) - Body ground

-

IG power supply

Engine switch off

Below 1 V

(d) Install the main body ECU (multiplex network body ECU) to the instrument panel junction block assembly.

Click here

(e) Measure the voltage and check for pulses according to the value(s) in the table below.

Tester Connection

Wiring Color

Terminal Description

Condition

Specified Condition

J9-2 (LSWR) - Body ground

L - Body ground

Rear door RH unlock detection switch input

Rear door RH unlocked

Below 1 V

J9-2 (LSWR) - Body ground

L - Body ground

Rear door RH unlock detection switch input

Rear door RH locked

Pulse generation

J8-2 (UL3) - Body ground

V - Body ground

Driver door key-linked unlock input

Driver door key cylinder turned to neutral position → on (unlock)

Pulse generation → Below 1 V

J8-6 (FLCY) - Body ground

P - Body ground

Front door courtesy light switch (for LH) input

Front door LH open

Below 1 V

J8-6 (FLCY) - Body ground

P - Body ground

Front door courtesy light switch (for LH) input

Front door LH closed

Pulse generation

J8-27 (FRCY) - Body ground

R - Body ground

Front door courtesy light switch (for RH) input

Front door RH open

Below 1 V

J8-27 (FRCY) - Body ground

R - Body ground

Front door courtesy light switch (for RH) input

Front door RH closed

Pulse generation

J8-29 (L2) - Body ground

P - Body ground

Driver door key-linked lock input

Driver door key cylinder turned to neutral position → on (lock)

Pulse generation → Below 1 V

2D-8 (ACT-) - Body ground

W - Body ground

Door lock motor unlock drive output

Door control switch or driver door key cylinder off → on (unlock)

Below 1 V → 11 to 14 V → Below 1 V

2D-6 (ACT+) - Body ground

P - Body ground

Door lock motor lock drive output

Door control switch or driver door key cylinder off → on (lock)

Below 1 V → 11 to 14 V → Below 1 V

2D-24 (LCTY) - Body ground

W - Body ground

Rear door courtesy light switch (for LH) input

Rear door LH open

Below 1 V

2D-24 (LCTY) - Body ground

W - Body ground

Rear door courtesy light switch (for LH) input

Rear door LH closed

Pulse generation

2B-14 (LSWL) - Body ground

V - Body ground

Rear door LH unlock detection switch input

Rear door LH unlocked

Below 1 V

2B-14 (LSWL) - Body ground

V - Body ground

Rear door LH unlock detection switch input

Rear door LH locked

Pulse generation

2B -1 (ACT-) - Body ground

B - Body ground

Door lock motor unlock drive output

Door control switch or driver door key cylinder off → on (unlock)

Below 1 V → 11 to 14 V → Below 1 V

2D-9 (ACT-) - Body ground

B - Body ground

Door lock motor unlock drive output

Door control switch or driver door key cylinder off → on (unlock)

Below 1 V → 11 to 14 V → Below 1 V

2B-4 (ACTD) - Body ground

B - Body ground

Door lock motor unlock drive output

Door control switch or driver door key cylinder off → on (unlock)

Below 1 V → 11 to 14 V → Below 1 V

2D-18 (ACT+) - Body ground

B - Body ground

Door lock motor lock drive output

Door control switch or driver door key cylinder off → on (lock)

Below 1 V → 11 to 14 V → Below 1 V

2B-2 (ACT+) - Body ground

R - Body ground

Door lock motor lock drive output

Door control switch or driver door key cylinder off → on (lock)

Below 1 V → 11 to 14 V → Below 1 V

2A-31 (RCTY) - Body ground

R - Body ground

Rear door courtesy light switch (for RH) input

Rear door RH open

Below 1 V

2A-31 (RCTY) - Body ground

R - Body ground

Rear door courtesy light switch (for RH) input

Rear door RH closed

Pulse generation

2B-12 (LSFR) - Body ground

P - Body ground

Front door RH unlock detection switch input

Front door RH unlocked

Below 1 V

2B-12 (LSFR) - Body ground

P - Body ground

Front door RH unlock detection switch input

Front door RH locked

Pulse generation

2B-13 (LSFL) - Body ground

B - Body ground

Front door LH unlock detection switch input

Front door LH unlocked

Below 1 V

2B-13 (LSFL) - Body ground

B - Body ground

Front door LH unlock detection switch input

Front door LH locked

Pulse generation

2B-16 (L1) - Body ground

B - Body ground

Door control switch assembly input

Door control switch assembly off → on (lock)

Pulse generation → Below 1 V

2A-7 (GSW) - Body ground

B - Body ground

Unlock detection input

Engine switch on (IG)

2.8 to 4.3 V

2A-39 (UL1) - Body ground

GR - Body ground

Door control switch assembly input

Door control switch assembly off → on (unlock)

Pulse generation → Below 1 V

CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

(a) Disconnect the J41 certification ECU (smart key ECU assembly) connector.

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

Tester Connection

Wiring Color

Terminal Description

Condition

Specified Condition

J41-4 (+B) - Body ground

V - Body ground

Battery power supply

Always

11 to 14 V

J41-18 (E) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

(c) Reconnect the J41 certification ECU (smart key ECU assembly) connector.

(d) Check for pulses according to the value(s) in the table below.

Tester Connection

Wiring Color

Terminal Description

Condition

Specified Condition

R1-26 (TSW5) - Body ground

G - Body ground

Back door opener switch input

Back door opener switch assembly (open switch) off → on

Pulse generation

R1-27 (TSW6) - Body ground

L - Body ground

Back door opener switch input

Back door opener switch assembly (lock switch) off → on

Pulse generation

CHECK AIRBAG SENSOR ASSEMBLY

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