Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Taillight Relay Circuit
DESCRIPTION
The main body ECU (multiplex network body ECU) controls the operation of the TAIL relay.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- Inspect the fuses for circuits related to this system before performing the following procedure.
-
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
.gif)
PROCEDURE
| 1. | PERFORM ACTIVE TEST USING TECHSTREAM |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Main Body / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Body Electrical > Main Body > Active Test| Tester Display | Measurement Item | Control Range | Diagnostic Note |
|---|---|---|---|
| Taillight Relay | Taillight relay | OFF or ON | - |
| Tester Display |
|---|
| Taillight Relay |
OK:
Taillights illuminate.
| OK |  | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
|
| 2. | CHECK HARNESS AND CONNECTOR (POWER SOURCE - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) |
(a) Disconnect the 2E instrument panel junction block assembly connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 2E-1 - Body ground | Always | 11 to 14 V |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
| 3. | INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
| *a | Component without harness connected (Instrument Panel Junction Block Assembly) | - | - |
(a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
Click here
(b) Connect a positive (+) lead from the battery to terminal 2E-1.
(c) Connect a negative (-) lead from the battery to terminal MB-14 (TRLY).
(d) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| 2C-32 - Battery negative (-) terminal | Always | 11 to 14 V |
| 2D-30 - Battery negative (-) terminal | Always | 11 to 14 V |
| OK | | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
| NG | | REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
Outside Handle Foot Light Circuit
DESCRIPTION The main body ECU (multiplex network body ECU) controls the outside handle foot lights. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Before replacing the main body ECU (multiplex networ ...
Low Beam Headlight Circuit
DESCRIPTION The main body ECU (multiplex network body ECU) controls the low beam headlights. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE:
Inspect the fuses for circuits related to this system be ...
Other materials:
Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Power Tilt And Power Telescopic Steering Column System: Data List / Active Test
DATA LIST / ACTIVE TEST READ DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may b ...
Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual > Automatic Transaxle System: Precaution
PRECAUTION PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE BATTERY TERMINAL NOTICE: When disconnecting the cable from the negative (-) battery terminal, initialize the following system(s) after the cable is reconnected: System See Procedure Lane Control System Pre-collision System ...
Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual
- For your information
- Pictorial index
- For safety and security
- Instrument cluster
- Operation of each component
- Driving
- Lexus Display Audio system
- Interior features
- Maintenance and care
- When trouble arises
- Vehicle specifications
- For owners
Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual
0.0119