G4X and VNT actuator?

[pcex]

Hello,

I was wondering if we got the ability to drive a basic Hella VNT actuator with the G4X? I'm not looking for precise boost control I just want to turn off my VNT turbo in traffic to avoid heat and fuel consumption if my idea is correct throttle response is not an issue for me it's for my daily driver gas engine, this would also help me with any over spool issues I may come across with pneumatic waste and such. 

[Vaughan]

You will need to figure out the pinout of the actuator you want to use as that will determine the control method from the ECU. In the picture below it looks like the top actuator would just need a single PWM signal from the ECU to control position and the position feedback would be over a CAN Bus whereas the bottom actuator would require an H bridge to drive (same control method as an E-Throttle) in which case you would need to use specific pins from the ECU, confirm the required current to ensure the ECU can supply it and you would have to set it up as an E-Throttle in the ECU as we don't currently have generic H-Bridge control software features.

[pcex]

Hello Vaughan,

Thank you for the reply yeah i saw this on the forum and i have the type that's on the top image the 412 model, i am not sure how to set up the can bus and pwm so i think i should invest in a dedicated vnt/vgt controller that can receive a duty cycle input and convert that to what is needed for the actuator, the product i foud was a digiboosters-s if you have any clue how i can set up my link without the dedicated controller it would be much appriappreciated.

[Vaughan]

The 412 model might be able to be controlled directly from the ECU, I don't know what the current (how many Amps) requirements are but theoretically you can just use an Aux Out setup as a GP PWM wired to that PWM input to control it. I would assume there is some smarts inside that actuator that would do closed loop position control given it's got enough smarts to have a CAN Bus output and I assume the CAN Bus output will feed back position info and maybe any faults or other information.

[pcex]

Thank you Vaughan

I will be working on it this week with my local link tuner and i will write back as soon as we have a breakthrough 

[pcex]

it seems as though the 412 model uses 12v PWM and that the can as you said was only for positioning and error codes, i may have to wire in a tip120 transistor and a 1k resistor to the aux output to get a 12v negative signal from the ground. Is there any 12v pwm pins on the link g4x wrx107 or should i go about a transistor? 

[Vaughan]

Any of Aux 1-10 will do PWM output pulling to ground with a 4k7? pullup to 12V when the pin is floating, any spare injector drives will do PWM pulling to ground but from memory they don't have pullups on them, any spare ignition drives will do PWM pulling to ground but from memory they only pull up to ~8V.

[pcex]

hello,

i used pin D22 Aux 7 Tumble Valves Open which is on my ecu i have tried various settings for PWM control, i also am resetting the program in the hella VNT device. im not using can bus on the device to make things less complicated. PWM on this pin just won't trigger the machine to actuate. i was wondering what settings am i doing wrong. 

also, i am really confused with the e-throttle relay i have one wired but it won't trigger during PWM test i saw the schematics and wired must have a mistake in the wiring. 

[Vaughan]

So you have power, ground and aux 7 wired up to the device and have Aux 7 set up as  GP PWM output with a non 0 duty cycle?

Have you managed to find any info on what frequency it expects?

If you have a CAN sniffer maybe try hooking up the CAN bus to see if it is sending anything and if so what it is sending

[pcex]

the turbo shop had told me the program in it had can bus turned off i don't think that would cause it not to work. 

[Vaughan]

9 minutes ago, pcex said:

the turbo shop had told me the program in it had can bus turned off i don't think that would cause it not to work

Sweet, that all looks like it should output 70%DC at 300HZ the whole time as I suspect An Volt 1 is always above 0.5V but just to confirm Aux 7 shows active and the correct frequency and duty values in it's runtimes when you are testing? Can you put a multimeter or even better a scope to confirm you have that signal on the wire you expect to?

[pcex]

i will have to buy a scope to confirm that or other means of testing, meanwhile, i was having some difficulties opening my throttle any suggestions? 

[Vaughan]

E-Throttle? have you done all the APS and TPS Calibration stuff?

[pcex]

APS calibration was a success however the TPS would not as the error code no tps movement comes up during calibration. I can confirm the e-throttle relay i wired works via the test, i also get the correct tps main and sub voltage readings when i manually open the throttle body however error code comes up for aux power 9/10 when i use the accelerator pedal. I suspect the car being a European model it has many variations in parts used in the engine bay to elaborate my throttle body is a bosh unit with output pins similar to gm throttle bodies and not what normally comes with sti or wrx bodies. my socket is a 6 pin square just like a gm and has a similar pinout whereas the sti are rectangular and the pinout order is totally different. i suspect the pwm frequency in my tune is set wrong, its at 1000 mhz right now soon i will try the 500 mhz as stated by gm throttle bodies and see if that can fix my problem. If all else fails i may have to buy a sti throttle body and socket as a direct replacement to the oem setup of my model. 

[Adamw]

21 minutes ago, pcex said:

however the TPS would not as the error code no tps movement comes up during calibration.

This means the ecu is comanding full power to the motor but has seen no change in voltage on the TPS sensors.  Attach a copy of your tune and a log of a tp cal attempt.  

[pcex]

Thank you for the info it will take me till tomorrow to attach the logs as the time zone but here is my tune 

cranking smoke fix.pclx

[Adamw]

At the time you saved that map the ECU was sending 70% duty cycle to the e-throttle motor but the TPS voltages show the throttle blade is still sitting in the closed/spring return position.  It is not a PWM problem, either you have the throttle pinout wrong or there is a bad connection between the ecu and throttle motor.  You can confirm you have the correct pins on the throttle body by measuring resistance between them.  The motor pins will have quite low resistance between them - most likely between say 4 and 20 ohms.  All the other pins will be 500ohms or higher.