Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Emergency Call Switch Illumination Circuit

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Audio & Visual & Telematics / Cellular Communication / Safety Connect System / Emergency Call Switch Illumination Circuit

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Depending on the parts that are replaced during vehicle inspection or maintenance, performing initialization, registration or calibration may be needed. Refer to Precaution for Safety Connect System.

    Click here

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

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (MAP LIGHT ASSEMBLY (MANUAL (SOS) SWITCH) POWER SOURCE)

(a) Disconnect the J157 DCM (telematics transceiver) connector.

(b) Disconnect the U12 map light assembly (manual (SOS) switch) connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

U12-5 (RRID) - Body Ground

Engine switch on (IG)

11 to 14 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J157-3 (SIG-) - U12-9 (GND3)

Always

Below 1 Ω

J157-3 (SIG-) or U12-9 (GND3) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

2.

INSPECT MAP LIGHT ASSEMBLY (MANUAL (SOS) SWITCH)

(a) Remove the map light assembly (manual (SOS) switch).

Click here

*a

Component without harness connected

(Map Light Assembly (Manual (SOS) Switch))

(b) Apply battery voltage to the connector and check that the roof console box assembly comes on.

OK:

Measurement Condition

Condition

Specified Condition

Battery positive (+) → U12-5 (RRID)

Battery negative (-) → U12-9 (GND3)

Always

Manual (SOS) switch illumination cones on
NG

REPLACE MAP LIGHT ASSEMBLY (MANUAL (SOS) SWITCH)

OK

3.

REPLACE DCM (TELEMATICS TRANSCEIVER)

(a) Replace the DCM (telematics transceiver) with a new one.

Click here

NOTICE:

  • The engine switch must be off.
  • Do not exchange the DCM (telematics transceiver) with one from another vehicle.
NEXT

PERFORM DCM ACTIVATION

    Unable To Connect To Call Center
    DESCRIPTION This may occur when the intensity of telephone radio frequency was very weak, or the safety connect system has a malfunction and a DTC is set. PROCEDURE 1. CHECK COMMUNICATION SERVIC ...

    Telephone And Gps Antenna (for Front Side)
    ...

    Other materials:

    Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Intelligent Clearance Sonar System: ECU Malfunction (C1611)
    DESCRIPTION If the clearance warning ECU assembly detects an internal malfunction during self-diagnosis, DTC C1611 is stored. DTC No. Detection Item DTC Detection Condition Trouble Area C1611 ECU Malfunction Sub-CPU abnormal signal Mirror check abnormal Clearance warning E ...

    Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Transfer System: Precaution
    PRECAUTION PRECAUTION (a) Prior to starting any work, clean the transfer assembly to prevent sand or mud deposits from entering the assembly. (b) When removing any light alloy components such as the transfer cover, do not pry on the component with a screwdriver or similar tool. Tap the component loo ...

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

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

    © 2026 Copyright www.lexusrx.net
    0.0098