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.

HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

CHECK OPERATION OF SPEEDOMETER
1. Drive the vehicle and check if the operation of the speedometer in the combination meter is normal
HINT: The vehicle speed sensor is operating normally if the speedometer display is normal.

NG: CHECK SPEEDOMETER CIRCUIT (See MALFUNCTION IN SPEEDOMETER )

OK: GO TO NEXT STEP.
INSPECT ECM (SPD VOLTAGE)
1. Shift the lever to the neutral position.
2. Jack up the vehicle.
3. Turn the ignition switch to ON.
4. Measure the voltage between the specified terminals of the E7 and E8 ECM connectors as the wheel is turned slowly.
  Standard:
  
  Fig 1: ECM Connector Terminals Specified Condition Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 2: Identifying ECM Connector Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
HINT: The output voltage should fluctuate up and down similarly to diagram on the left when the wheel is turned slowly.

Fig 3: Vehicle Speed Sensor Output Voltage Graph
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO NEXT STEP.

REPLACE ECM (See ECM (3MZ-FE) )