Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Vehicle Speed Signal Circuit between Navigation ECU and Combination Meter
DESCRIPTION
The navigation ECU receives a vehicle speed signal from the combination meter assembly.
HINT:
- A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter assembly. The signal is changed to a pulse signal at the transistor in the combination meter assembly. Each ECU controls its respective systems based on this pulse signal.
- If a short occurs in any of the ECUs or in the wire harness connected to an ECU, all systems in the following diagram will not operate normally.
WIRING DIAGRAM
PROCEDURE
| 1. | CHECK COMBINATION METER ASSEMBLY (OUTPUT WAVEFORM) |
| (a) Check the output waveform. (1) Remove the combination meter assembly with the connector still connected. (2) Connect an oscilloscope to terminal J10-19 (+S) and body ground. (3) Turn the engine switch on (IG). (4) Turn a wheel slowly. (5) Check the signal waveform according to the condition(s) in the table below.
OK: The waveform is similar to that shown in the illustration. HINT: When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows. |
|
| NG |  | GO TO METER / GAUGE SYSTEM |
|
| 2. | INSPECT NAVIGATION ECU (INPUT WAVEFORM) |
| (a) Check the input waveform. (1) Remove the navigation ECU with the connector(s) still connected. (2) Connect an oscilloscope to terminal J153-9 (SPD) and body ground. (3) Turn the engine switch on (IG). (4) Turn a wheel slowly. (5) Check the signal waveform according to the condition(s) in the table below.
OK: The waveform is similar to that shown in the illustration. HINT: When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows. |
|
| OK | | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
AVC-LAN Circuit
DESCRIPTION Each unit of the navigation system connected to the AVC-LAN (communication bus) transmits switch signals via AVC-LAN communication. If a short to +B or short to ground occurs in the AVC-LA ...
Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter
DESCRIPTION The stereo component amplifier assembly receives a vehicle speed signal from the combination meter assembly to control the ASL function. HINT:
A voltage of 12 V or 5 V is output from ea ...
Other materials:
Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Rear Spoiler: Reassembly
REASSEMBLY PROCEDURE 1. INSTALL CENTER STOP LIGHT ASSEMBLY Click here 2. INSTALL NO. 2 REAR SPOILER SEAL HINT: When installing the No. 2 rear spoiler seal, heat the rear spoiler using a heat light. Heating Temperature Item Temperature Rear Spoiler 20 to 30°C (68 to 86°F) CAUTION: ...
Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual > Lumbar Support Adjuster Assembly: Installation
INSTALLATION CAUTION / NOTICE / HINT CAUTION: Wear protective gloves. Sharp areas on the parts may injure your hands. HINT:
Use the same procedure for the RH side and LH side.
The following procedure is for the LH side.
PROCEDURE 1. INSTALL FRONT SEATBACK HOOK Click here 2. INSTALL LUMBAR ...
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
0.0085