4-62 FI SYSTEM DIAGNOSIS Step 1 (When indicating P1651-H:) 1 1) Turn the ignition switch OFF. 2) Lift and support the fuel tank. (5-3) 3) Check the TO sensor coupler for loose or poor contacts. If OK, then check the TO sensor lead wire continuity. 4)Disconnect the TO sensor coupler. 1 5)Check the continuity between Red wire A and Black wire B. If the sound is not heard from the tester, the circuit condition is ! OK. 6)Disconnect the ECM coupler. 1 E ! 7)Check the continuity between Black wire B and terminal L. L 8) Also, check the continuity between B/Br wire C and terminal S. TOS lead wire continuity: Continuity () P 09900-25008: Multi-circuit tester set 09900-25009: Needle pointed probe set M Tester knob indication: Continuity test () (Black) (Gray) A ECM coupler (Harness side) Is the continuity OK? S YES Go to Step 2. NO Black wire shorted to VCC, or B/Br wire open. 9)After repairing the trouble, clear the DTC using SDS tool. (4-27)