Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Terminals Of Ecu

TERMINALS OF ECU

CHECK OUTER MIRROR CONTROL ECU ASSEMBLY (DRIVER DOOR)

(a) Disconnect the N4 outer mirror control ECU assembly (driver door) connector.

(b) Measure the voltage and resistance 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

N4-14 (BDR) - Body ground

L - Body ground

+B power supply

Always

11 to 14 V

N4-6 (CPUB) - Body ground

L - Body ground

+B power supply

Always

11 to 14 V

N4-5 (SIG) - Body ground

Y - Body ground

Ignition power supply

Engine switch off → on (IG)

Below 1 V → 11 to 14 V

N4-7 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

(c) Reconnect the N4 outer mirror control ECU assembly (driver door) connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

z12-3 (MR) - Body ground

SB - Body ground

Power retract mirror motor drive voltage

Outer rear view mirror assembly (driver door) being retracted

11 to 14 V

Outer rear view mirror assembly (driver door) stopped

Below 1 V

z12-11 (MF) - Body ground

LG - Body ground

Power retract mirror motor drive voltage

Outer rear view mirror assembly (driver door) returning

11 to 14 V

Outer rear view mirror assembly (driver door) stopped

Below 1 V

z12-1 (MV) - z12-10 (M+)

V - R

Vertical mirror motor drive voltage

Driver door mirror surface moving upward → stopped

11 to 14 V → Below 1 V

z12-10 (M+) - z12-1 (MV)

R - V

Vertical mirror motor drive voltage

Driver door mirror surface moving downward → stopped

11 to 14 V → Below 1 V

z12-10 (M+) - z12-9 (MH)

R - BR

Horizontal mirror motor drive voltage

Driver door mirror surface moving right → stopped

11 to 14 V → Below 1 V

z12-9 (MH) - z12-10 (M+)

BR - R

Horizontal mirror motor drive voltage

Driver door mirror surface moving left → stopped

11 to 14 V → Below 1 V

z12-4 (HTR+) - z12-12 (TRN-)

B-G - W

Mirror heater relay drive voltage

Mirror heater switch (rear window defogger switch) on

11 to 14 V

z12-5 (VDD) - N4-7 (GND)

O - W-B

Mirror position sensor power supply

Engine switch on (IG)

4.75 to 5.25 V

z12-6 (VSSR) - N4-7 (GND)

W-B - W-B

Mirror position sensor signal

Engine switch on (IG)

0 to 5 V

z12-13 (HSSR) - N4-7 (GND)

Y-B - W-B

Mirror position sensor signal

Engine switch on (IG)

0 to 5 V

CHECK OUTER MIRROR CONTROL ECU ASSEMBLY (FRONT PASSENGER DOOR)

(a) Disconnect the M4 outer mirror control ECU assembly (front passenger door) connector.

(b) Measure the voltage and resistance 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

M4-14 (BDR) - Body ground

G - Body ground

+B power supply

Always

11 to 14 V

M4-6 (CPUB) - Body ground

GR - Body ground

+B power supply

Always

11 to 14 V

M4-5 (SIG) - Body ground

B - Body ground

Ignition power supply

Engine switch off → on (IG)

Below 1 V → 11 to 14 V

M4-7 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

(c) Reconnect the M4 outer mirror control ECU assembly (front passenger door) connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

z13-3 (MR) - Body ground

SB - Body ground

Power retract mirror motor drive voltage

Outer rear view mirror assembly (front passenger door) being retracted

11 to 14 V

Outer rear view mirror assembly (front passenger door) stopped

Below 1 V

z13-11 (MF) - Body ground

LG - Body ground

Power retract mirror motor drive voltage

Outer rear view mirror assembly (front passenger door) returning

11 to 14 V

Outer rear view mirror assembly (front passenger door) stopped

Below 1 V

z13-1 (MV) - z13-10 (M+)

V - R

Vertical mirror motor drive voltage

Front passenger door mirror surface moving upward → stopped

11 to 14 V → Below 1 V

z13-10 (M+) - z13-1 (MV)

R - V

Vertical mirror motor drive voltage

Front passenger door mirror surface moving downward → stopped

11 to 14 V → Below 1 V

z13-10 (M+) - z13-9 (MH)

R - BR

Horizontal mirror motor drive voltage

Front passenger door mirror surface moving right → stopped

11 to 14 V → Below 1 V

z13-9 (MH) - z13-10 (M+)

BR - R

Horizontal mirror motor drive voltage

Front passenger door mirror surface moving left → stopped

11 to 14 V → Below 1 V

z13-4 (HTR+) - z13-12 (TRN-)

B-G - W

Mirror heater relay drive voltage

Mirror heater switch (rear window defogger switch) on

11 to 14 V

z13-5 (VDD) - M4-7 (GND)

O - W-B

Mirror position sensor power supply

Engine switch on (IG)

4.75 to 5.25 V

z13-6 (VSSR) - M4-7 (GND)

W-B - W-B

Mirror position sensor signal

Engine switch on (IG)

0 to 5 V

z13-13 (HSSR) - M4-7 (GND)

Y-B - W-B

Mirror position sensor signal

Engine switch on (IG)

0 to 5 V

    Problem Symptoms Table
    PROBLEM SYMPTOMS TABLE NOTICE: If the battery voltage is low, the mirror heater function may not operate. When "Operation of Electrical Items Restricted." is displayed on the multi-information display ...

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

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