Hyundai Sonata LF: Engine Control System / Injector Troubleshooting
The three waveforms below are taken from the #1 and #4
injectors. The top waveform is from the high side (feed side) of the #1
and #4 injectors, while the middle waveform is from the low side (ground
side) of the #1 injector and the bottom waveform is from the low side
of the #4 injector.
The middle waveform is the same as the top waveform because
there is no ground for the circuit. With no current flowing in the
circuit, the #1 injector is not energized and fuel does not flow.
The bottom waveform shows that ground is supplied and there
is a voltage drop across the #4 injector. With current flowing in the
circuit, the #4 injector is energized and fuel flows.

Other information:
Description
Passenger Airbag (PAB) module is located in the passenger
crash pad. This PAB contains 2 firing squibs of airbag and 1 firing
squib of active vent. Depending of crash speed or the tightening of seat
belt, it is decided a timing about both 2 firing squibs of airbag and 1
firing squib of active vent...
C..