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https://www.youtube.com/watch?v=kuDQ_MINuTk

I'm a bit confused with my AVCS. I think they are not working! Long story short!

I put the avcs solenoid connector off while engine running and connected with Scal.
I measured the voltage on the connector it was milivolt levels.
I measured the duty cycle and it was %49
I measured the frequency and it was 299.9


So duty cycle and freq. values seems okay but I was thinking to measure 12 volts? Am I wrong?
On the output testing mode when the fuel5(RAVCS) triggered I hear no clicking noise.

Did I make a mistake on my avcs wiring or bad solenoids?

One side of the solenoid should be connected to a fused +12V supply so would read 12V all the time, with the ignition on.

The other side is a low-side drive driven, as you realise, as a PWM output. So it will be switching at the calibrated frequency and duty cycle between ground and open circuit. So if you measure between that pin and ground you'll see, um, not a lot.

If you measure across the two pins then at 50% duty and 300Hz, you ought to see something approximating 6V. And if you use output testing and turn the drive "on" you should measure 12V - again, though, only across the 2 pins.

Thanks Tim.

When the engine is off and ignition is ON I don't see any voltages.
Now I tried the output testing mode, fuel output base states and I have measured 7.99 V between two pins
Sure it is not enough to trigger avcs solenoid.

That makes me to think that I have used a wrong shotky diode may be?
I dont even remember what type or where diode is on my wiring :/
It was probably a SB560 but not sure.

The diode shouldn't have any effect on this if installed right! It goes from the ecu drive output pin to +12V and only conducts when the output is turned off and the back emf from the OCV needs somewhere to go (essentially the output pin sees a voltage >12V and the diode allows the energy to be dissipated into the 12V wiring).

If you're only seeing 8V across the 2 pins when you use output testing, either your battery is somewhat discharged (!) or the wiring is suspect/incorrect - like you put a diode, and a non-schottky type, in series or something?

Shottky diode should pull up the voltage 0.3v.
Interesting. I'm %100 sure it was working when I swap the spec c engine. DCCD was also working! Now I check the DCCD and it is not working as well :/
Both DCCD and AVCS is not working now. If it is not an ecu hardware related issue I have to find where did I put the shottkies on my wiring.
This is a lot of job even at lockdown.

Its been 5 years I dont even remember which connectors. Hopefully I have some entries here;
viewtopic.php?p=3650

I will get rid of shottkies first to see if I can get +12V. I cant lift up the car now. It would be easier to check DCCD side.

I found my notes. Is that right?

Can't 100% read your notes, but if the top connection is to the ECU (aux output?) and "B137" is your connected to battery volts, then your diode is back to front.

TimH wrote: ↑Mon May 11, 2020 4:51 pm Can't 100% read your notes.

I couldn't read as well =) AFAIK shootky anode to ECU FUEL6-8 output and cathode to 12V.
I think I found the diode bulk here. I hope so

Your anode and cathodes sound like they're correct then. Cathode is the stripe on the diode and I really would check that you've wired it right, and that it is a schottky type.

Not a tailor made but it looks okay? It is a SB560.