1)
Specification : 0.3 ~ 0.5 Ω at 20℃68℉)
BASIC INSPECTION
Before performing the inspection of APS, make sure that the follwing items :
① Contact resistance, corrosion, bent or broken terminals, connector connection, loose wires etc.
② Leakage with the return line
③ Fuel quality
CHECK PROCEDURE
1. Injector
① Inspect the the severe pollution of injector nozzle.
② Copper washer condition.
③ Fuel leakage.
☞ Replace the injector
If more than 2 injectors are failure. the engine starting is impossible or the engine stall.
2. Resistance check
Connect the ohmmeter probes to the terminal 1 and the terminal 2, measure the resistance
Specification : 0.3 ~ 0.5 Ω at 20℃68℉)
3. Analysis for the injector signal waveform
The nozzle has opened by the electrical pulse, the energizing current is reduced to a lower holding value. The Injection is terminated when the solenoid valve is no longer triggered and closes as result. The switching on the ECM, the current profile of the injector with booster, clear, and recharge phases is the follwing step. Capacitor in ECM is function to charge for activating the injectors
① Capacitor discharge -> ② Pull up current -> ③ Charge (7A) -> ④ Hold in current (12±1A) -> ⑤ Charge (⑥,⑦ Hold in control current)
① Signal waveform for the high side, the low side, the current
② Signal waveform for the high side, the low side
③ Signal waveform for the low side, the current
④ Signal waveform for the low side, the capacitor charge
