Known Good IAC Waveform For Those Interested
#1
Known Good IAC Waveform For Those Interested
So for any interested I thought I would post an image of the waveform of my Idle Air Control valve so you could see how the VCM is controlling it during a “Key On” event for a “Known Good” IAC.
Setup: This is a snapshot of a “KEY ON” event (KOEO) taken with a Snap-On Verus.
Channel 1 = COIL A HIGH Control
Channel 2 = COIL A LOW Control
Channel 3 = COIL B HIGH Control
Channel 4 = COIL B LOW Control
Looking at the voltage spikes at the top of the green trace and the bottom of the blue trace….If you look to the left of the frame divider (position 160) you can see where COIL A (channels 1 & 2) is/are “in the lead” as compared to COIL B (channels 3 & 4). This is the IAC motor winding the pintle down, extending it towards the pintle seat, in preparation for start-up. At position 160 you see where the pintle has stopped because it has contacted the pintle seat. Then to the right of 160 you see where the VCM reverses the field and COIL B “takes the lead” as the pintle retracts.
Though not shown here, when I turned the key off COIL B was “in the lead”. The pintle only retracted (did not extend) as the module put the pintle in position for the next “KEY ON” event.
Setup: This is a snapshot of a “KEY ON” event (KOEO) taken with a Snap-On Verus.
Channel 1 = COIL A HIGH Control
Channel 2 = COIL A LOW Control
Channel 3 = COIL B HIGH Control
Channel 4 = COIL B LOW Control
Looking at the voltage spikes at the top of the green trace and the bottom of the blue trace….If you look to the left of the frame divider (position 160) you can see where COIL A (channels 1 & 2) is/are “in the lead” as compared to COIL B (channels 3 & 4). This is the IAC motor winding the pintle down, extending it towards the pintle seat, in preparation for start-up. At position 160 you see where the pintle has stopped because it has contacted the pintle seat. Then to the right of 160 you see where the VCM reverses the field and COIL B “takes the lead” as the pintle retracts.
Though not shown here, when I turned the key off COIL B was “in the lead”. The pintle only retracted (did not extend) as the module put the pintle in position for the next “KEY ON” event.
#4
Congrats on the S/O Verus. I see them on You Tube vid's where the experts like the guy on South Main Auto, Eric the carguy, and others are able to do magic with a Verus. Keep us updated on all the neat info you get from that machine. Maybe one Christmas!
#6
Ha! Don't I wish. Paul is a stud and I have learned a ton from him over the last couple of years.
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