Inspection Procedure

WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.

CHECK COMBINATION METER ASSY
INSPECTION USING OSCILLOSCOPE
1. Check the input signal waveform.
  1. Remove the combination meter assy.
  2. Connect the oscilloscope to the terminals C7-32 and body ground.
  3. Start the engine.
  4. Check the signal waveform according to the condition (s) in Fig 2 below.
    
    Fig 2: Signal Waveform Conditions Chart
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard: As shown in Fig 3

Fig 3: Combination Meter Assy Wave Form Graph
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT: As the vehicle speed increases, the cycle of the signal waveform narrows.

Fig 4: Combination Meter Assy Conditions Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

B: Go to step 2

C: Go to step 3

A: CHECK AND REPLACE COMBINATION METER ASSY
INSPECT SKID CONTROL ECU ASSY
1. Check voltage.
  1. Shift the shift lever to neutral.
  2. Jack up either of the front wheels.
  3. Turn the ignition switch to ON.
  4. Measure voltage between terminals S7-2 of the skid control ECU assy and body ground when the front wheel is turning slowly.
    
    Fig 5: Inspect Skid Control ECU Assy
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard voltage:

Fig 6: Skid Control ECU Voltage Graph
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Voltage is generated Intermittently.

NG: CHECK AND REPLACE SKID CONTROL ECU ASSY

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR
INSPECT ABS & TRACTION ACTUATOR ASSY
1. Check voltage.
  1. Shift the shift lever to neutral.
  2. Jack up either of the front wheels.
  3. Turn the ignition switch to ON.
  4. Measure voltage between terminals S1 -26 of ABS & traction actuator assy and body ground when the front wheel is turning slowly.
    
    Fig 7: Inspecting ABS & Traction Actuator Assy
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard voltage:

Fig 8: ABS & Traction Actuator Voltage Graph
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Voltage is generated intermittently.

NG: CHECK AND REPLACE ABS & TRACTION ACTUATOR ASSY

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR