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Subaru AVCS Cam Solenoid Current & Frequency

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I've been doing a little research ahead of wiring and configuring the dual AVCS cam control solenoids on my M130 controlled EJ257 and thought it would be good to share/validate the information I already have and answer a couple of final questions.

I plan to run the solenoids with half bridge outputs from the M130 configured as a low side drive at 300Hz as per the BRZ pre-configured package.

Having reviewed the base car wiring diagrams both solenoid wires terminate at the ECU so I've been unable to confirm which wire is positive and which is negative. I understand that the solenoids are not polarity sensitive.

I'm unsure what the maximum expected power consumption is for each solenoid so if anyone had any experience here that would be helpful. I'm of the impression that it's fairly low (1-2amps?) due to the light gauge OE wiring and general component function so plan to use 20ga A55 wire with a single 6A fuse and see how this goes. Do you think this is sufficient?

Hi Ray,

Run them at 300Hz and 14V as the Actuator Reference Voltage. Be careful with the minimum duty cycle as well, as having it too high will get the cams moving out of sync with the Aim, This will vary with oil pressure as well, so always do your Cam Setup with the oil pressure up.

I haven't found an issue with which pin has the power supplied to it on these actuators, I do however wire them to have the Halfbridge on Pin 1/A and the Batt+ on Pin 2/B (as per MoTeC's standard convention) I have done a few cars this way and have not had an issue with it. Subaru supplies power to Pin 1 on the connectors by default, it just means that you may need to have the Actuator Polarity as Inverted.

I use 20G on mine (EJ207) without a separate fuse, they are run through the same loom as the injector supply and feed off of my PDM.

Thanks for the info. I only just read your post and had already configured the inlet cams at 300Hz and 12v and quickly iterated the PID terms towards the values from the Subaru BRZ base package as I didn't have a lot of time and I expected the hardware to be fairly similar.

The feed forward percentage is right around 50% but was difficult to refine to the point where the cam position would stabilize. I iterated the value to 1dp accuracy so that the cam advance change was fairly slow and this seemed close enough for the PID to take care of the rest. I'll try to refine this a little further when I'm setting up the exhaust cams tomorrow. I left the dead band and smoothing at zero with min and max dc values set at 20 and 80.

Straight away the cam position signals were noisier than I would have expected and possibly in response to a similar trait, the PID terms in the BRZ package of 900/2500/60 seemed odd as they're far in excess of the typical values that the M1 help screen suggested. I iterated the proportional gain up towards 900 and quickly found the BRZ values to give good response but was still left with a significant error and imbalance between banks of 2-5 degrees. At this point I decided to add in the "I" term from the BRZ package with good effects.