DESCRIPTION
This circuit detects the engine switch on (IG) or off condition, and sends it to the main body ECU (multiplex network body ECU).
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
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PROCEDURE
1. | CHECK FOR DTC (SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function)) |
(a) Clear the DTCs.
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(b) Check for DTCs.
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Result | Proceed to |
---|---|
Smart Access System with Push-button Start (for Start Function) DTCs are not output | A |
Smart Access System with Push-button Start (for Start Function) DTCs are output | B |
B | ![]() | GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) |
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2. | READ VALUE 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 / Data List.
(e) Read the Data List according to the display on the Techstream.
Body Electrical > Main Body > Data List Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
---|---|---|---|---|
IG SW | Engine switch on (IG) signal | ON or OFF | ON: Engine switch on (IG) OFF: Engine switch off | - |
Tester Display |
---|
IG SW |
OK:
Normal conditions listed above are displayed.
OK | ![]() | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
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3. | 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 |
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4. | INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
(a) Remove the instrument panel junction block assembly.
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(b) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
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(c) Measure the resistance according to the value(s) in the table below.
*a | Component without harness connected (Instrument Panel Junction Block Assembly) | - | - |
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
2E-1 - MB-32 (IG) | Battery not connected to 2A-17 and 2B-3 | 10 kΩ or higher |
2E-1 - MB-32 (IG) | Battery positive (+) → 2A-17 Battery negative (-) → 2B-3 | Below 1 Ω |
OK | ![]() | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
NG | ![]() | REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Occupant Classification System: Data List / Active Test
DATA LIST / ACTIVE TEST 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 be dis ...
Lexus RX (RX 350L, RX450h) 2016-2025 Owners Manual > Child safety: Riding with children
Observe the following precautions when children are in the vehicle.
Use a child restraint system appropriate for the child, until the child becomes
large enough to properly wear the vehicle's seat belt.
It is recommended that children sit in the rear seats to avoid
accidental contact
wi ...