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Home >> Lexus >> 1995 >> SC 400 V8-4.0L (1UZ-FE) >> Repair and Diagnosis >> Heating and Air Conditioning >> Testing and Inspection >> Component Tests and General Diagnostics >> Temperature Control Switch Circuit
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Temperature Control Switch Circuit





By turning the temp. control switch, the set temperature of the A/C can be adjusted in steps of 1°F (USA) or O.5°C (Canada). Turning the switch fully will set the A/C to MAX. COLD or MAX. HOT.
The ECU calculates the set temperature from the combination of Hi (5 V) or Low (0 V) terminals SET 1 - 5 of the temp. control SW and displays the set temperature on the LCD display.

If a malfunction occurs in the temp. control SW circuit, malfunctions such as not being able to set the desired temperature occur.

Diagnostic Chart:




Wiring Diagram:






Inspection Procedure - Step 1:




Step 2:




Step 3:




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