MS3Pro and 2JZ Stepper Motors

[shaodome]

For some reason I can't get the 2jz stepper motor to work on the MS3Pro. This is a 6 wire stepper with two 12v wires in the middle.

On the MS3 and the MS2 stepper chips you have to disconnect the 12v line or it would mess up the firmware. Then the Unipolor stepper would be wired as such:

http://www.msextra.com/forums/viewtopic ... 80#p276980

Now on the MS3Pro, if I try to wire it as the above the idle motor does not function.

In my testing I turned off the idle control and set the programmable outputs for the IAC1 and then for IAC2. Per the docs, one of these should be HIGH and one should throw ground when activated. In my case, neither does this. I even tried it on another MS3pro and the same behavior occurs. It's almost like the stepper chip isn't connected (like on 3.0 boards if you don't make the S12 jumper underneath).

[nathaninwa]

Mine worked briefly with the 12v unhooked. It quit working and I switched to a pwm motor and got with Matt about a warranty on it. I was able to send it in and it got fixed

Just like you, mine would not operate as programmable outputs either

Tbh, I like the stepper control much better

[shaodome]

I'm a fan of stepper motors for idle control as well....

This is weird though with the stepper. I NEVER had the 12v hooked up as I set it the same was as the old MS3x setup. I bought both of these MS3Pro's that I tested at around the same time too. Once actually belongs to the race car from BDPC, the other is my personal one. I just triple checked the wiring and there is no shorts and all the pins have continuity from the IAC plug to the ECU.

[nathaninwa]

I goofed on there. Was out with the kids and thoughts/typing didn't jyve. I actually prefer the pwm setup after running both and when I buddy's stepper starting having issues we went the pwm route and never looked back

Email Matt about, might be a warranty deal

I had mine fixed because I'm running out of I/O's

[Matt Cramer]

We had them working OK with the 12 volt supply hooked up and the mode set to moving only - trouble was finding the correct pinout.

One other issue I've seen is that the stepper output can act erratic if the logic ground is not hooked up or is hooked to a different spot from the power ground.

[shaodome]

We had them working OK with the 12 volt supply hooked up and the mode set to moving only - trouble was finding the correct pinout.

One other issue I've seen is that the stepper output can act erratic if the logic ground is not hooked up or is hooked to a different spot from the power ground.

I have an RMA that ben issued me on these units for the injector driver upgrade and was actually just thinking about walking with them to the MegaMeet (as I'm still driving my car a little bit). Before boxing them up, I'll double check that logic ground as I find it extremely UNLIKELY that two ECUs exhibit the same behavior. Will advise...

See you guys this weekend!