New MIMA Thread

[nasphere]

Originally Posted by retepsnikrep

I tried altering duty to 75% it did not initiate the start cycle so need to look again at that signal.

Is it possible the other signals change duty on startup, like ENGTRQ?

You could setup a "missing pulse detector" circuit to toggle a scope to snag the duty cycle when it pops over 55% on start up.

What about the 75% being idle speed for smooth idle? I've never prodded into the signals in my car yet.

EDIT:

I think Mike may have an answer for us with starting the engine. The anomaly in the code before the update caused a startup in PIMA mode after 25 seconds of idle stop. Mike, could you explain the conditions that caused an engine start? pretty please??? thanks in advance!

[Right Lane Cruiser]

What changes would have to be made to one of the plug'n'play MIMA systems to implement regen on idle by modifying the duty cycle of mamode1?

[retepsnikrep]

Mike's system doesnt allow any mima signals to work when car is travelling less than 19mph so that the first thing he would have to change. Then he would have to modify the MAMODE1 signal duty. Probably not hard but would require users to upgrade or reflash their mima chip. He's a busy man as we all know.


Nasphere I have already captured the start up data i need to check i have it implemented correctly. You can view it on one of the other mima threads. we have looked at ENGTRQ before it never seems to change.

Mike's annomaly may have just been accidental application of assist which will start the car after a couple of seconds. The actual start cycle is different in that it's instant and the motor is clearly being fed a lot of current for a very short period to start it spinning.

[retepsnikrep]

I can confirm that

CMDPWR duty cyle 50%
MAMODE1 duty cycle 85%
MAMODE2 Low

Initiates start cycle which revs engine instantly to about 2k

Not sure how useful this is but interesting, might be good for quick starts with EV conversion using insight motors

So my take on the signals is

'Standby Mode = CmdPwr 50% MaMode1 50% MaMode2 High
'Assist Mode = CmdPwr 51-90% Mamode1 25% MaMode2 Low
'Regen Mode = CmdPwr 49-10% MaMode1 37.5% MaMode2 High
'Start Mode = CmdPwr 50% MaMode1 85% MaMode2 Low

[3-Wheeler]

Originally Posted by retepsnikrep

Mike's system doesnt allow any mima signals to work when car is travelling less than 19mph so that the first thing he would have to change......

Hi Peter,

You may need to revise that statement in light of the existence of MIMA-CL out there.

I can definitely regen below 19 mph as MIMA-CL does not make use of VSS (the velocity signal).

There is a negative side-effect to this however, depending on the circumstances of how/when you regen....

Depending, sometimes the ECM sees the engine slowing down too much due to regen, and then it tries to feed in more gas to compensate, which lowers the MPG's.

It becomes a delicate operation to do properly.

Jim.

[Right Lane Cruiser]

Is that limitation only for regen? I was under the impression that assist would work at any speed.

[retepsnikrep]

Jim

I meant Mike's commerical product which uses the VSS signal.

I don't have any limits on my own system either.

[Mike Dabrowski 2000]

MIMA works even stopped in idle, the 19MPH disable is for PIMA, which would restart the car if it autostopped, so I disable PIMA under the 19mph that autostop begins to work.
Boy this makes me want to start fooling with the MIMA code, but I have to stay focused on the grid chargers.

[Eli]

Yep. You can even start the car with MIMA if you want to.

One thing I've noticed -

If you rev the engine with MIMA in neutral, sometimes the engine will die instead of catching itself at idle. Anyone ever noticed that before, or is it a problem with my car?

I've actually started using it as a new feature. When it dies like this, it will re-start if I put it in gear just like auto stop. So it's like a poor man's FAS - I'll often do it in the mornings when sitting at a light and the car isn't warmed up yet(so no autostop).

[nasphere]

Originally Posted by retepsnikrep

So my take on the signals is

'Standby Mode = CmdPwr 50% MaMode1 50% MaMode2 High
'Assist Mode = CmdPwr 51-90% Mamode1 25% MaMode2 Low
'Regen Mode = CmdPwr 49-10% MaMode1 37.5% MaMode2 High
'Start Mode = CmdPwr 50% MaMode1 85% MaMode2 Low

This is VERY important information! Thank you so much!

I wish we could get ahold of all the engineering docs for this car or the IMA alone. I bet there's alot more modes and features we could use.

Originally Posted by 3-Wheeler

Depending, sometimes the ECM sees the engine slowing down too much due to regen, and then it tries to feed in more gas to compensate, which lowers the MPG's.

I think the TPS signal may have more to do with it. I remember reading on this forum about a modded TPS signal which gave alot better lean burn at more of a throttle range. Does anyone know the specs on the TPS as far as resistance?