MPGuino release one workspace

[dcb]

Just to be clear, you have to unplug the connector from the injector, otherwise you will see 12 volts on both leads.

Also we are talking about two wires going to the same injector that you are measuring, right?

[Wonderboy]

Thank you for the speedy response..

Yes, I am taking the plug out of the injector(s) (I tried each one just to be sure), alligatoring the negative tester probe to the car body... just ground somewhere...and I'm sticking the positive probe into each of the two injector plug leads. Using DC on the multimeter of course. Both wires going into the plug look the same too :-/

[dcb]

Do you think you could post a picture of the injector? And maybe a link to the cars schematic? You are sure you are looking at an injector? I have no clue about these model specific things so I have to ask a lot of stupid questions.

[SVOboy]

You mean delete everything from the window I pasted the mpguino code into? Fairly sure...I'll play with it more in a few hours and let you know.

[Wonderboy]

And here's my VSS tap just for good mesaure..


I should probably just post a bunch of pictures now that I have my dash torn apart.

Edit:
Here is an illustration of exactly what is happening

[dcb]

Ok, well there are only two wires to choose from on any particular injector, so I would say try one, if you don't get a signal on the uS field on the instant raw data screen then try the other one.

re vss, I think you are looking for a blue and white wire per Technical Support , go to the very bottom and look up your vehicle by year.

[Wonderboy]

I'm pretty sure I've got the VSS lead right.

From Rostra:

VSS Wire: Transaxle 3 Pin Plug or Under Coin Tray Black Connector
VSS Wire Color: Red/Yellow

None of the VSS leads are blue nor white, but there is a red/yellow one, which is the one I tapped.

[dcb]

My bad, on the vss, was looking at celica. Hey, I have one of those meters

Ok, so the only way to differentiate the injector leads is by left v/s right? No color cues? You willing to try them both if necessary and let us know which one works?

[dcb]

Originally Posted by top_down

I will say that the display is hard to read in bright sunlight and almost impossible to read when it is hot.

Having gained a little more experience, I'm starting to like the green displays more myself. They seem more readable even when hot. Need to do a little homework before changing recommendations though (check prices/temperature ranges/availability).

[SVOboy]

I fixed my issue just by creating a new mpguino file, so that's good. Unfortunately I can't find through board tact switches, so it might take a while to get the actual thing going and happy.

[awillard69]

Here's a tip, scavenge those switches from old VCR's or similar devices. You may find a few other items of interest as well.

[Wonderboy]

So the wires that go into my injectors ARE actually colored differently upon closer inspection (red stripe on black & orange stripe on black). I chose the orange one, but I can't even tell if it is the correct one because I can't seem to get the LCD working.

The backlight is on, and it gets dimmer when I push any of the buttons, then it gets brighter when I release the button. Wrong switches maybe?

[dcb]

WB, if your guino came up on the desktop but not by the vehicle, I suggest starting with reprogramming the guino. You have to be very deliberate about hooking up the power, flashing the power on and off can give it a case of amnesia. In severe cases you have to reload the bootloader (no fun). I probably need to add that caution to post 1. It should definately not get appreciably dimmer when pressing any button.

[RuHaSs]

Wonderboy,
Found this for you, it should help tons.

RapidShare: Easy Filehosting

You should be able to use any non full black wire from any of the injector leads.

The VSS seems to be the red/yellow one as you have correctly found.

[Wonderboy]

Whoa, that's a big find right there. I don't think I need it anymore, but that should be sticky for any toyota driver wanting to install a guino.

My problem remains as I retire this project for the evening:

I rechecked the wiring, and resoldered a couple ground connections, but the display is still flickery at times, but stays solid if you don't touch anything, and I reconfigured the buttons the other way... I still don't quite know how tactile switches are configured, nor do I know if my switches are normally on/off. This was never specified in the plans, and i'm not sure if it even matters. I only have 2 leads from each of the switches in the circuit, and the circuit goes across the switch on a side where the pins are visible:

[dcb]

Yah, Ruhass doesn't say much, but when he does it is usually pretty good. I have to figure out how to view a RAR file and take a look

The buttons are Normally open, one lead of each button should go to ground, the other leads to analog 3,4, and 5, one pin per button. What are you using for an arduino?

[dcb]

Scope showed up today, it is a cute little portable 15mhz job

I scoped the power downstream of the 7805 and did not see anything, zoomed into max frequency and minimum voltage. It was rock solid, even while hitting switches and the blower and the starter, running or not, and tried the horn, nothing phazed it.

I scoped the injector, typical injector signal. I scoped pins 2/3 and they appeared well protected at the max resolution of the scope. The only issue I saw was the low end of the signal, and this may mean a hardware change is still needed. This is basically what I saw when zoomed in a bit on the pulse:


So the theory is that the mosfets (or whatever switches ground) drop the voltage to just about zero initially, but then the injector (being a large inductor) starts letting more current through, and the voltage rises to something approaching a volt. We *might* need to condition the signal a bit more to ensure we are solidly in LOW mode on those pins. Need to research it a bit more first.

I will have to wait till I fix the batteries on the scope to do anything interesting with VSS, this is a pretty cool tool though

[SVOboy]

Having button issues. The middle button (on a4) works fine and I can scroll left through the contrast screen on .66, however the left and right don't work. Both register 0 resistance from the iduino pin to ground while the middle one registers 1. Know what's up with this?

[dcb]

your middle button should be cycling through the numbers, left and right should be scrolling left and right. Can you double check the wiring and pin assignments?

Sounds like the LCD is working though

[SVOboy]

Yeah, troubleshooting for an hour has me here: Tapping the grounds from the left and right buttons against the pins on the iduino perform the appropriate function, but the buttons seem to be always closed. Is it possible they're just no good? Could they have been damaged in soldering?