Meter / Gauge System Operating Light Control Rheostat Does Not Change Light Brightness

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING DATA LIST (Rheostat value (A/D))

INSPECT LIGHT CONTROL RHEOSTAT

CHECK WIRE HARNESS (COMBINATION METER - LIGHT CONTROL RHEOSTAT)

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch on (IG) and the tester ON.
   

3. Read the Data List according to the prompts displayed on the tester.
   
   

   Combination meter

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Rheostat value (A/D)	Light control rheostat volume / Min.: 0, Max.: 255	Light control rheostat Min. position: 0 Light control rheostat Max. position: 255	-

   OK:

   Light brightness can be changed within the specified range.
   

1. Remove the light control rheostat.
   

2. Measure the resistance of the rheostat.
   

   Standard resistance:

   Tester Connection	Rheostat Position	Specified Condition
   1 (E) - 3 (RV)	Max.	8 to 12 kΩ
   1 (E) - 3 (RV)	Mid.	4.7 kΩ
   1 (E) - 3 (RV)	Min.	0 to 50 Ω

1. Disconnect the E22 meter connector.
   

2. Disconnect the E2 rheostat connector.
   

3. Measure the resistance of the wire harness side connectors.
   

   Standard resistance:

   Tester Connection	Specified Condition
   E22-26 (SW1) - E2-7 (T)	Below 1 Ω
   E22-27 (SW2) - E2-3 (RV)	Below 1 Ω
   E22-30 (TC) - E2-5 (TC)	Below 1 Ω
   E22-34 (SW3) - E2-1 (E)	Below 1 Ω
   E22-26 (SW1) or E2-7 (T) - Body ground	8 to 12 kΩ
   E22-27 (SW2) or E2-3 (RV) - Body ground	8 to 12 kΩ (position Max.)
   E22-30 (TC) or E2-5 (TC) - Body ground	Below 1 Ω (Tail cancel OFF)
   E22-34 (SW3) or E2-1 (E) - Body ground	10 kΩ or higher