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.

READ VALUE OF HAND-HELD TESTER (TACH)
1. Check output value of ECM.
  1. Connect the hand-held tester to DLC3.
  2. Turn the ignition switch to ON and push the hand-held tester main switch to ON.
  3. Select the item "ENGINE SPD" in the DATA LIST and read its value displayed on the hand-held tester.
OK: There is almost no difference in the displayed engine rpm value.

NG: GO TO ENGINE CONTROL SYSTEM

OK: Go to next step.
CHECK COMBINATION METER ASSY
(REFERENCE) INSPECTION USING OSCILLOSCOPE
1. Check the input signal waveform.
  1. Remove the combination meter assy with connectors still connected.
  2. Connect the oscilloscope to the terminals C7-31 and C7-1 of combination meter assy.
  3. Start engine.
  4. Check the signal waveform according to the condition (s) in Fig 2 below.
Fig 2: Combination Meter Assy Signal Waveform Conditions Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard: As shown in Fig 3

Fig 3: Combination Meter Assy Signal Waveform Graph
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: CHECK AND REPLACE COMBINATION METER ASSY

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR