Canister Closed Valve
Hello, Working on some scope training at a shop today and we are taking a look at the Vent valve of this vehicle. When commanded on it buzzes ( not the Clunk) that I was expecting. Also the pcm is always commanding a pulse KOEO and KOER, enough to light techs noid light. Is this normal? any ideas?diag.net/file/f3rojvl17…
I'm sure others are more knowledgeable than me on this but I'll give it a shot. The PCM is constantly monitoring the circuit for faults with the small duty cycle your seeing there. This is normal operation. Recently had an 07 Elantra with an EVAP issue and during my diag I had too scope the purge an vent control circuits. My operation was the same and was normal. Also not trying to give a silver…
Just to make sure I was clear ( I cound not find the closed valve on the list of components for the PICO scope so I listed Purge), with Vent in the notes. I was testing the Vent / closed valve.
Gotcha. But yes the PCM tests both components the same way.
This capture is from a 2014 Elantra. CH B is the VCT solenoid voltage. In CH C, I connected a jumper wire on the solenoid's control wire. The amp clamp is on the jumper wire and I am tapping the jumper wire to ground. You can see the amperage draw, thru the winding, that is required to create the magnetic field, to lift the solenoid's pintle from it's normally closed position.
That's a great image of how the solenoid reacts to manually grounding the circuit. Do you happen to have the same capture when the solenoid is commanded on by the PCM during a bi-directional command?
Sorry Randy, I didn't try to use the bi-directional command because I found that the Snap On scanner does not always support the bi-directional command for all makes and models, for all of the solenoids.