AC–34 AIR CONDITIONING SYSTEM – TROUBLESHOOTING Blinking Light F D Engine Coolant Temperature Sensor Circuit CIRCUIT DESCRIPTION This sensor detects the coolant temperature and sends the appropriate signals to the A/C amplifier. These signals are used for warm up control when the engine is cold. Diagnostic Sensor Check Detecting Condition | Trouble Area Open or short in engine coolant temperature sensor circuit. | • Engine coolant temperature sensor • Harness or connector between engine coolant temperature sensor and A/C amplifier • A/C amplifier WIRING DIAGRAM A/C Amplifier 5 V Engine Coolant Temp. Sensor (For A/C System) LG-R 11 LG-R 16 TW IG 1 A13 2 1 V-W 4 V-W 9 SG IG 1 A13 N08816