IN–28 INTRODUCTION – HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS 6 CIRCUIT INSPECTION How to read and use each page is shown below. • Diagnostic Trouble Code No. and Detection Item • Circuit Description The major role and operation, etc. of the circuit and its component parts are explained. DTC 24 Intake Air Temp. Sensor Circuit • Indicates the diagnostic trouble code, diagnostic trouble code set parameter and suspect area of the problem. CIRCUIT DESCRIPTION The intake air temp. sensor is built into the volume air flow meter and senses the intake air temperature. The structure of the sensor and connection to the ECM is the same as in the engine coolant temp. sensor shown on page EG-424. If the ECM detects the diagnostic trouble code "24", it operates the fail safe function in which the intake air temperature is assumed to be 20°C(68°F). DTC No. | Diagnostic Trouble Code Detecting Condition | Trouble Area 24 | Open or short in intake air temp. sensor circuit for 0.5 sec. or more | • Open or short in intake air temp. sensor circuit • Intake air temp. sensor • ECM WIRING DIAGRAM Intake Air Temp. Sensor (Inside Volume Air Flow Meter) 2 P-L 1 BR-B Engine Control Module ⊕ 5V 45 THA E3 +WA- 66 E2 E3 E1 F4648 • Wiring Diagram This shows a wiring diagram of the circuit. Use this diagram together with ELECTRICAL WIRING DIA- GRAM to thoroughly understand the circuit.