general information - Martin Nez

FI SYSTEM DIAGNOSIS 4-51“C21” (P0110-H/L) IAT SENSOR CIRCUIT MALFUNCTIONDETECTED CONDITIONC21 Output voltage is not within the followingrange.0.15 V Sensor voltage < 4.85 VP0110 Sensor voltage is higher than specifiedHvalue.Sensor voltage is lower than specifiedLvalue.POSSIBLE CAUSE• IAT sensor circuit open or short• IAT sensor malfunction• ECM malfunction• IAT sensor circuit open or ground circuit open• IAT sensor circuit shorted to groundIAT sensorECMDgIATB/BrE2INSPECTIONStep 1 (When indicating C21:)1) Turn the ignition switch to OFF.2) Lift and support the fuel tank. (5-3)3) Check the IAT sensor coupler for loose or poor contacts.If OK, then measure the IAT sensor voltage at the wire sidecoupler.4) Disconnect the coupler and turn the ignition switch ON.15) Measure the voltage between Dg wire terminal A andground.6) If OK, then measure the voltage between Dg wire terminal Aand B/Br wire terminal B. IAT sensor input voltage: 4.5 – 5.5 V(+ Dg – - Ground)(+ Dg – - B/Br) 09900-25008: Multi-circuit tester set Tester knob indication: Voltage ()1VIs the voltage OK?YES Go to Step 2.• Loose or poor contacts on the ECM couplerNO (terminal Q or S)• Open or short circuit in the Dg wire or B/Br wire