10. Malfunction indicator light (MIL) driving stage (see Table 1-12) Table 1-12 11. Driving stage of stepper motor coil 1 and 2 (see Table 1-13) Table 1-13 44 Diagnostic Trouble Code (DTC) Trouble Location or Type P0650 MIL control circuit S/N Operation Test Results Actions 1 Ignition switch in position ON. Next step 2 Open the instrument panel, remove the MIL bulb, and measure the voltage of the jack. Is the voltage about 12V? Yes Next step No 5 (check hot wire) 3 Check the MIL bulb for normal operation with a multimeter. Yes Next step No Replace bulb 4 Connect an adapter between the ECU and the harness.
Check for open or short circuit between pin J1-63 of the ECU and the input connector of the MIL bulb with a multimeter. Yes Repair or replace harness No Replace ECU 5 Check the fuse for the heating circuit of the oxygen sensor. Is the fuse OK? Yes Replace fuse 6 Check for open or short circuit between pin 87 of the main relay and pin (1) of the MIL jack with a multimeter. Yes Repair or replace harness No Next step 7 Repair or replace the main relay and its circuit. S/N Operation Test Results Actions 1 Turn on the ignition switch, and do not start the engine. Next step 2 Disconnect the stepper motor from the harness.
Measure the resistance between pin (1) and pin (2), as well as between pin (3) and pin (4) of the stepper motor with a multimeter. Is the resistance between 40Ω and 80Ω? Yes Next step No Replace idle speed actuator 3 Measure the resistance between pin (1) and pin (2), as well as between pin (3) and pin (4) of the stepper motor with a multimeter. Is the resistance infinite? Yes Next step No Replace idle speed actuator 4 Measure the resistance between pin (1) and pin (2), as well as between pin (3) and pin (4) of the stepper motor connected with the harness with a multimeter. Is the resistance about 12V?
Yes Replace idle speed actuator No Next step 5 Connect an adapter between the ECU and the harness. Check for open or short circuit between pin J1-34, J1-33, J1-53, J1-54 of the ECU and the pin (1), (2), (3), (4) of the stepper motor with a multimeter. Yes Repair or replace harness No Replace ECU