Microtech lt10s PWM output wiring?

[VendableFall]

Hey everyone, ive searched heavily but cannot find and answer I find comforting!

I have a lt10s, and im looking to install a Bosch Idle Air Control Valve (PN) 0280140516, its a 2 wire PWM unit. Currently i am using one aux out to controll the thermo fans so have two spare (aux out #2 and aux out #3).


reading through old threads like below, i can see CrUZida, mentions "two dedicated wires for idle speed"
http://www.toymods.org.au/forums/thr...with-microtech
http://www.toymods.org.au/forums/thr...lco-Idle-Motor
leading me to believe i need to wire up aux out #2 and #3 to the two wires on the IACV

Then in this post he warns against running a solidnoid without a relay,
http://www.toymods.org.au/forums/thr...lp-VVT-and-a-c
my understanding is a relay will not switch fast enough for a PWM signal..

but when looking at the microtech wiring diagrams:
http://microtechefi.com/download/LTX...206%20CYLw.pdf
they attach one side of the IACV to output #1 and the other to a 12v source (this is how i currently have it wired)

i have not powered the car on yet for fear of blowing my ECU.

any help would be greatly appreciated as i am in a holding pattern untill i find a definitave answer!

[jondee86]

Maybe I can clear some of this up

- A 2-wire (Bosch type) ISCV requires a switched 12V supply and a connection to one PWM capable ECU aux output.
- A 3-wire Toyota (4AGE 20V type) ISCV requires a switched 12V supply and connection to two PWM capable ECU outputs.
- ECU aux outs are only capable of switching a few amps to ground, and that will be fine for an ISCV. However, for switching higher currents like cooling fans, a relay must be interposed to protect the aux out from overload.
- To drive your 2-wire ISCV you will need to program the ECU to vary the PWM duty cycle according to engine cooling water temperature. There should be a 2D table you can call up. A PWM frequency of around 200Hz should work.

In general, the ECU does not supply 12V for any accessories. It switches 12V to ground to control relays, solenoids and other low current control components. The maximum current ratings for PWM capable and non-PWM capable outputs will be set down in the documentation for your ECU.

Cheers... jondee86

[The Witzl]

The issue here is that you have a Microtech, which are not the most "flexible" of ECUs. Microtech are configured from factory to suit specific engines and setups, and if you want to change that you usually have to send it back for re-configuration.
I would talk to Microtech directly and see what they say.

Or sell it and buy something more user friendly like an Adaptronic

[VendableFall]

Maybe I can clear some of this up

- A 2-wire (Bosch type) ISCV requires a switched 12V supply and a connection to one PWM capable ECU aux output.
- A 3-wire Toyota (4AGE 20V type) ISCV requires a switched 12V supply and connection to two PWM capable ECU outputs.
- ECU aux outs are only capable of switching a few amps to ground, and that will be fine for an ISCV. However, for switching higher currents like cooling fans, a relay must be interposed to protect the aux out from overload.
- To drive your 2-wire ISCV you will need to program the ECU to vary the PWM duty cycle according to engine cooling water temperature. There should be a 2D table you can call up. A PWM frequency of around 200Hz should work.

In general, the ECU does not supply 12V for any accessories. It switches 12V to ground to control relays, solenoids and other low current control components. The maximum current ratings for PWM capable and non-PWM capable outputs will be set down in the documentation for your ECU.

Cheers... jondee86

Thanks, much appreciated!

The issue here is that you have a Microtech, which are not the most "flexible" of ECUs. Microtech are configured from factory to suit specific engines and setups, and if you want to change that you usually have to send it back for re-configuration.
I would talk to Microtech directly and see what they say.

Or sell it and buy something more user friendly like an Adaptronic

Haha yeah, well it came with the car, I would think about changing ECU if they made some kinda plug adapter. Ive just spent the last month installing the alarm so im getting sick of wiring.

Im going to see how she is to drive with an IACV and IAT and some tuning. If I am still not happy, ill look at changing the ECU.

[VendableFall]

Hey everyone,

Just thought I would update this with my findings:

I struggled for a while to get this IACV working, turn out Polarity does matter with this iacv (bosch 0280140516) according to http://forums.turbobricks.com/showthread.php?t=187309 .

Also for this IACV to work properly you will need a flyback diode as shown here http://www.vems.hu/wiki/index.php?pa...en%2FAudiSidle .

Happy spanner spinning

[dumbass]

good luck getting idle control working on a microtech hahaahahahaha

[VendableFall]

good luck getting idle control working on a microtech hahaahahahaha

well i did, works pretty well! cold starts without any accel pedal, starts at 1800rpm and slowly lowers to idle, also compensates for lights and A/C....

I guess not all people are cut out to work on cars...

[dumbass]

i fking hate cars , work on them everyday haha