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 ILLUMINATION
1. Operate the rheostat and check that the quantity of light for the combination meter assy, audio system and A/C control panel etc. are normally changed.
Fig 1: Illumination Conditions Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

B: CHECK AND REPLACE COMBINATION METER ASSY

A: Go to next step.
CHECK COMBINATION METER ASSY
1. Remove the combination meter assy with connectors still connected.
2. Turn the ignition switch to ON.
3. Measure the voltage between terminals C8-1 and C8-19 of combination meter assy connector.
Fig 2: Checking Combination Meter Assy
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard voltage: 0.1 - 4.1 V

OK: CHECK AND REPLACE COMBINATION METER ASSY

NG: Go to next step.
INSPECT LIGHT CONTROL RHEOSTAT
1. Check continuity between terminals 1 (TC) and 3 (T) of light control rheostat when light control rheostat operation as shown in chart below.
  
  Fig 3: Light Control Rheostat Continuity Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check light control rheostat resistance.
  1. Measure the resistance between terminals 1 (TC) and 3 (T) of light control rheostat.
    Standard resistance: Approx. 10 kΩ
  2. Measure the resistance between terminals 1 (TC) and 4 (RV) of light control rheostat when operating the light control rheostat. Check that the resistance value changes continuously.
  Standard resistance:
Fig 5: Light Control Rheostat Resistance Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE LIGHT CONTROL RHEOSTAT

OK: Go to next step.
CHECK HARNESS AND CONNECTOR
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: CHECK AND REPLACE COMBINATION METER ASSY