Power FC not saving??

[Cam_Ron]

The issue I'm having these days is with the power fc not saving any changes that I make.
I'm told that the power fc needs to be powered for 1 second after the engine is shut down in order to save any new settings.

To do this I suspect that I need to use the M-Rel pin to trigger a relay to send power to +B, +B1. Can any body confirm this, or provide some insight?

---------- Post added at 06:52 PM ---------- Previous post was at 06:51 PM ----------

So I found a diagram from Toyota that shows how the M-rel circuit is supposed to work.

The part that confuses me is when I metered out the M-Rel pin with it not wired to anything at all its output mirrored 12v switched ignition. As in key off no power, key on full switched power. When the key was turned off, voltage dropped to zero immediately with no 1 second delay?

Is the absence of voltage at the M-Rel pin meant to trigger the the relay??

---------- Post added at 06:53 PM ---------- Previous post was at 06:52 PM ----------

I do have a stock ecu to compare the pin, but where I have changed the wiring from batch to sequential to run the 2jz pfc, I wont be able to run the car with it.

From my research when functioning properly the M-Rel pin is supposed to power +b, +b1 for an additional few seconds by triggering a relay to do so. If this is the case, and the M-Rel pin doesn't stay on when switched ignition is cut, it wont work correct?

Is there any way to use the absence of voltage to trigger a relay ? I've never had to do it that way?



All additional wiring seems to be good, and battery is in good shape.

---------- Post added at 06:54 PM ---------- Previous post was at 06:53 PM ----------

This is strange, because I know the tune when I got it was not the factory default, and I have gotten it to save one other time so I could scale for the 550's but thats it. (And I'm not sure what kind of magic it took to do this as no changes in wiring were performed).
From this I suspect that the power fc still has the ability to save changes.

Laptop, datalogit, and hand controller have been confirmed to be connected and are able to make changes that take immediate effect while running. The issue is that they are erased when the engine is shut down.

Here is the link that I learned about the saving function:

http://www.paulr33.com/powerfc-faq/powerfc-faq.htm#56

Im not really sure where to go from here?

 

[aphxero]

yeah the mrel needs to be right. So it's like this. The ecu sees a voltage input on IGSW, it then sends power out of mrel to close the main relay. The main relay jumps power from the battery to +b. I've seen some ecu where mrel stops working. with stock ecu it's no big deal but pfc is picky. Is your +b staying on after you turn off igsw? So if the relay stays closed it won't matter that the ecu turns off the coil. Have you checked out the relay itself?

That pic you posted is right. And if it saved this could be whats happening.

 

[Cam_Ron]

I never had a relay connected to M-rel in the past (This is in a fc3s that I've put a 1jz into). Is the M-rel pin functioning correctly if its output mirrors +12v switched? As in, it is +12 with the key on and 0 with if off?

The reason I ask is that is what I observed when I metered it out on the pfc and with a stock ecu as well.

I'm not sure how the M-Rel pin is supposed to trigger the relay to provide power to +B and +B1 after the ignition is switched off when it doesn't stay on?

If the output of a properly functioning M-Rel pin is what I described would I not need a time delay relay (Immediately energizes, stays energized for a period after trigger is back to its default signal)?

 

[aphxero]

You're right but mrel should be hanging open for a sec after you shut the key off. When the igsw goes off the ecu hangs it open with power from batt. Now I've wired many pfc into many cars that aren't supposed to have it and I've seen burnt out mrel circuit before. I even got it to save. Before we explore other ideas I need to know how the following is wired.

Injector powers
ignition powers
+b powers for iscv, vsv's, and o2
batt to ecu
igsw
mrel
+b

I know we talked about some of that but let's get a clear picture of whats going on in one post.

 

[Cam_Ron]

Injector, ignitor, +b, +b1, and igsw are all wired to 12v switched through a relay from the ignition switch.

batt has its own dedicated path to battery constant through a fuseable link.

What are the odds that my stock jzx90 ecu and this power FC both have blown M-Rel circuits?

 

[aphxero]

odds are low. Just do me a favor and try hooking it all up correctly. It might be due to the igsw being tied to +b. Think about the "if/then" of all 4 power circuits. PFC is picky as hell with that. The stock ecu will always behave normally as long as batt is on.

If this doesn't work just try putting a toggle to +b and timing it when you shut the key off.

 

[Cam_Ron]

I'm not sure what you mean by hook it up correctly? What should I change? (aside from separating igsw and +B?)

Thats interesting that the PFC doesn't like them to all be on the same +12v circuit? Is it not electrically the same if they are connected to +12v together or separately?

As for the toggle switch idea, I already tried that but perhaps my timing was off? For that to work I would have to switch +B, +B1 to battery constant while simultaneously turning off the ignition?

Also, did you get my PM? If so what are your thoughts?

 

[aphxero]

well if the ecu sees igsw turn off and +b goes off too it's like wtf? It needs it to hang to move setting from ram to rom. So with switch it's have to be key off, then wait a sec and turn +b off. But it might also need to see the ground from the relay coil. By hook it up I meant exactly like factory.

 

[Cam_Ron]

I pulled the dash back out tonight and had another look at everything. I took a four pin relay and wired it exactly as shown in the diagram above. The power fc hand controller never shut off using the batt wire. I switched that pin on the relay to a direct line to the battery and it did what it was supposed to. With the key off the power stayed on for a second or so and then shut off.

But... it still wont save? I was wondering wtf was going on so I metered out the M-Rel pin while connected to the relay and properly functioning. With the key on it was at switched 12v power but a bit lower (10.5X V) than if taken directly at the ignition switch (11.9+). When the key was turned off it would dip down to 8.xxV and then die a second or so after. This was enough power to keep the hand controller lit up for the extra second or two.

Is is possible that although the circuit is functioning properly now, there isn't enough voltage for the PFC to save? If so, does this point to a grounding issue?

Any possible advice would be appreciated.

 

[aphxero]

Yeah it sure does. How well is the motor grounded? And have you checked the resistance in that relay when it's closed? I've seen shitty relays pull the voltage down 2v before. So that relay you put in was shutting down +b right? And yeah pfc doesnt like to save with low volt.

Remember the ecu grounds all flow through the motor to the chassis. Do you have a ground on the back of the head? And where are your harness grounds on the engine?

 

[Cam_Ron]

I figured it out!!

I turns out that I wired in the relay correctly, m-rel was able to trigger it properly, but for some reason the power fc didn't like what was happening when the +12v was cut (key off). It all goes back to a fuckey ignition switch!!! I don't have another on hand, so I rigged up a toggle switch which does double duty as an immobilizer. With the key on, unless the switch is on the ecu doesn't recieve any power. When I turn the key off with the toggle still in the on position, the car continues to run. As soon as I turn the toggle off, the M-rel pin triggers the relay to close the contact and keep the pfc on for a second or so.

After all of this screwing around its a thing of beauty to have my settings save.
Big thanks to you aphxero for all your help.