MPGuino rebooting and freezing also... Power issue?

[tygertec]

On my old Corolla, the VSS signal is actually generated right there in the combination meter from the speedometer cable. I think I'm as close as I can get. Plus, the speed portion of the MPGuino was working perfectly when it was working.

I ran a new ground straight to the negative battery terminal and still had the same exact problems.

I definitely agree with you about the 14.5V not being the problem. I'm thinking that maybe the voltage regulator has blown/gone bad and I need to replace it. Bummer.

[tygertec]

I tested the voltage regulator with a voltmeter. With the car off, it was reading +11.9V on the input side and +4.95V on the output side. With the car on (and the unit frozen I might add), input V was +13.5V and output a steady +4.95V.

I know output is supposed to be +5.1V. Is 4.95 a teensy weensy bit too low?

Also, I just performed the tests outlined here:

Mpguino tests - EcoModder

and here are the results:

A-B Inf
A-C Inf (Interesting. Not grounded?)
A-D 49.K (supposed to be INF. short?)

B-A 13.43M (yes, M)
B-C Inf
B-D 14M (That can't be good)

C-A Inf
C-B Inf
C-D Inf

D-A 48.9K (why so low?)
D-B Inf (Weird. B-D is 14M. Hmmm...)
D-C Inf

1-2 5M
1-3 5M
2-1 17.16M
2-3 10.54K
3-1 Keeps going up. Now around 18M.
3-2 10.54K

So I feel like these tests indicate that there's some kind of problem on the board. A visual inspection made my me doesn't reveal anything obvious. Perhaps one of the components is blown.

[dcb]

(sorry, been on vacation for a few days)

You can send this unit back for a reflash (via S.A.S.E) if you like, no guarantees where a donation and gift are concerned (would have to charge a lot more for that) but we will reflash it and test it and take a look. I don't know exactly why it konks out on ignition, even with the battery tap? Maybe a decent sized rcl circuit for the power taps might help too, sound like some sort of unusuall spike if a reflash doesn't fix it.

[tygertec]

(No worries. I'm glad you took a vacation. :-))

Sent it off today. Thanks!

One thing I was going to try but didn't get a chance was plug it in while the car was already on. If it didn't freeze then there was probably some sort of spike or brownout issue. But I forgot to try that. :-o

I don't have a DC generator or I would have tried to test how it reacted to various voltage states.

So when it gets back hopefully it will work like a champ. Otherwise I'll look into creating an rlc circuit (though I'd probably need a few hints on which cap, resistor, inductor to purchase.)

Thanks for all your help!

[hu_man]

Sounds like you may have a connection problem at the battery I would clean the post real good. It does not take much to drop the power to the other connections when the starter is engaged about 1000 amps or more will rush to the starter and then come down to the cranking amps any resistance at the battery will cause a voltage drop. I know that the battery should be checked also at cranking for the voltage drop it should not drop below 10.5 volts, this may give you a clue to the problem hope it helps.
Hugh

[tygertec]

That's a really good idea Hugh. Thanks! I'll test the voltage while cranking and see what it looks like. Plus I'll clean the posts. Then when my MPGuino gets back we'll see what happens.

[tygertec]

I checked the connection to the RJ11 box with a voltmeter and with the car off voltage was 12.65, nice and strong. While cranking, dropped down to about 10.6V one time and 11V the second time. Then the voltage shoots up to around 14.5V with the car on. So it seems like I've got a good strong connection. But I'm still going to clean the terminals again anyway.

Voltage of course fluctuates slightly with the car on and even with the car off when I turn on/off different devices that draw current.

[JohnNeiferd]

Mine has been having similar issues. It'll lock up and restart itself after several minutes or it'll be working fine and randomly restart itself. 1993 Geo Metro, tapped to the injector wire by the injector and into the VSS signal at the ECU. Oddly enough, sometimes the vehicle speed will go crazy and will jump around going from 50 to 89mph when I'm going 55. I'm not sure if its radio frequency interference from houses or what, but that is probably a separate issue. However, I just put a fairly good size aluminum heatsink on the back of the power regulator today so that should keep it much cooler, I'm hoping that solves the restarting problem. I'll let you know what happens.

[tygertec]

I'm interested to know if the heatsink helps you out any. Are you using an enclosure with your mpguino? When I get mine back I'd like to find out how to put it in an enclosure with a temperature-controlled fan in the back, perhaps in conjunction with a heatsink.

I'm not sure about the VSS signal oddity either. You could take a look at this thread:

http://ecomodder.com/forum/showthrea...ates-4236.html

[orange4boy]

Hello,

I've got the same issues. I'm using a spiffie kit in a 93 Toyota Previa. V.75
I already took mine apart and resoldered everything. It gets worse and worse. Crashes sooner and sooner in the same way described by Tygertec.

I even have mine hooked up to a 3.5 AH battery separate of the car.

One thing I noticed is that my injectors have 12V on each wire with the ignition on. car not running.

Recently the gph started to run like it was attache to the vss. Adding to itself.

Could this be a connection to ecu wires issue? I didn't solder the VSS. although I did just solder the inj.