4-38 FI SYSTEM DIAGNOSIS 4) Disconnect the IAP sensor coupler. 1 5) Turn the ignition switch ON. V 6) Insert the needle pointed probes to the lead wire coupler. 7) Measure the voltage at the Red wire and ground. 8) If OK, then measure the voltage at the Red wire and B/Br wire. IAP sensor input voltage: 4.5 – 5.5 V (+ Red – - Ground) (+ Red – - B/Br) 09900-25008: Multi-circuit tester set 1 09900-25009: Needle pointed probe set Tester knob indication: Voltage () V Is the voltage OK? YES Go to Step 2. • Loose or poor contacts on the ECM coupler NO (terminal A or S). • Open or short circuit in the Red wire or B/Br wire. E Step 1 (When indicating P0105-H:) 1 1) Turn the ignition switch OFF. L 2) Lift and support the fuel tank. (5-3) P 3) Check the IAP sensor coupler for loose or poor contacts. If OK, then check the IAP sensor lead wire continuity. SAM 4) Disconnect the IAP sensor coupler. 1 5) Check the continuity between Red wire A and G/B wire B. If the sound is not heard from the tester, the circuit condition is OK.