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CSXRT4
11-03-2009, 02:13 PM
Ok I cant seem to figure out what this is. My power board for my SMEC keeps smoking, ive traced wires down and everything seems to be wired correctly. It only happens if the engine runs and then stalls without turning the key off. If the key is off, I turn it on and it will not smoke. Then if I start it and do something to kill the engine without turning the key off, a little spot near the 14pin connector starts glowing red and eventually smoking through the gel covering. It hasn't seemed to effect the functionality of the SMEC, everything still runs ok but obviously there is and issue that needs to be fixed.

Any ideas???
turbovanmanČ
11-03-2009, 02:34 PM
Check powers and grounds but use an old headlight, test lights don't draw enough amps and can lead to grounds that are marginal showing up good. Found many a bad ground using a headlight.

Maybe the alt is bad too?

You get an old sealed beam headlight, the one's where the low beam is burned out, attach 2 wires then you can go tracing power and ground circuits, the high beam pulls like 15 amps and will find a bad ground, :thumb:
CSXRT4
11-04-2009, 02:51 PM
Simon you are awesome :thumb:

It ended up being a bad ground at the fuel rail/sensor ground. I guess it wasnt getting enough ground through the intake manifold or something, I relocated the ground to the block and all is well now.

Thanks dude
turbovanmanČ
11-04-2009, 03:53 PM
No problemo, glad you found it. :D

Did you use the headlight trick?
risen
11-04-2009, 10:57 PM
No problemo, glad you found it. :D

Did you use the headlight trick?

The headlight is a great idea. I'm going to make sure that I remember that one. Though, I guess you'd have to be careful where you use it.
turbovanmanČ
11-04-2009, 11:47 PM
The headlight is a great idea. I'm going to make sure that I remember that one. Though, I guess you'd have to be careful where you use it.

How so?
risen
11-05-2009, 09:02 AM
How so?

Well, you wouldn't want the ground wire to be like 22ga or 20ga. 15 amps would melt something like that in a couple of seconds.
turbovanmanČ
11-05-2009, 08:00 PM
Well, you wouldn't want the ground wire to be like 22ga or 20ga. 15 amps would melt something like that in a couple of seconds.

Well it doesn't really matter, mine has 18 gauge wire on it, its great for finding dead shorts as the headlight takes the load and nothing burns up. I showed my neighbour this as he kept blowing fuses, put this in, glows bright, then he traced wiring etc until the light went out, found it, harness had rubbed through, :thumb:
butchsuppe
11-05-2009, 08:24 PM
It's too bad more people don't understand the headlight concept, I know it's hard to explain why it's a great way to test circuits. :nod:
turbovanmanČ
11-05-2009, 10:52 PM
It's too bad more people don't understand the headlight concept, I know it's hard to explain why it's a great way to test circuits. :nod:

Exactly, :clap:
CSXRT4
11-06-2009, 12:26 AM
No problemo, glad you found it. :D

Did you use the headlight trick?

Yup, used a headlight and probed grounds from the 2 SMEC connectors. Found it instantly lol
turbovanmanČ
11-06-2009, 01:00 AM
Yup, used a headlight and probed grounds from the 2 SMEC connectors. Found it instantly lol

Awesome, glad it worked out for you, :clap:

BTW, something happened to the Ostrich, it wouldn't let you program it, so Moates gave me a brand new one instead of fixing it, :partywoot:
CSXRT4
11-06-2009, 01:11 AM
Awesome, glad it worked out for you, :clap:

BTW, something happened to the Ostrich, it wouldn't let you program it, so Moates gave me a brand new one instead of fixing it, :partywoot:

Thats weird :( But thats cool that they gave you a new one though. Did they give you a V2?

I just bought a new one a couple weeks ago, I got back into doing some SMEC stuff on another project and there is no way I am going back to pulling the chip out every time I need to flash a change haha. The ostrich is an amazing tool, and the best thing is you can use it on any platform that uses and EPROM based ecu. I bought a moates burn2 also, I was sick of my piece of crap willem burner giving me crap :amen:
turbovanmanČ
11-06-2009, 01:32 AM
Thats weird :( But thats cool that they gave you a new one though. Did they give you a V2?

I just bought a new one a couple weeks ago, I got back into doing some SMEC stuff on another project and there is no way I am going back to pulling the chip out every time I need to flash a change haha. The ostrich is an amazing tool, and the best thing is you can use it on any platform that uses and EPROM based ecu. I bought a moates burn2 also, I was sick of my piece of crap willem burner giving me crap :amen:

It worked great for months, then it just wouldn't let me program.

Yep, got the new smaller version, also bought a Burn 2 as well. I bought the remote mount board awhile ago and just got Zip sockets for it, makes life a breeze, :thumb:
CSXRT4
11-07-2009, 09:53 PM
Well the problem came back and now the SMEC is finally toast :(

Not sure why it went away and then came back but I think I may have found another culprit. We put a MSD Blaster 2 coil on when we first started the project. Just as a "lets try this because nothing else is working" we put a stock coil on and of course the problem went away :banghead:

So now im wondering if the MSD coil needs a ballast resistor??? I searched around and everybody says that you dont need one on a TD but why would this coil be toasting my SMEC? I defective exchanged the MSD coil for a new one at advance auto and im going to see if the new one does the same thing. If the problem is still there I guess ill have to try a ballast resistor.
risen
11-08-2009, 04:20 PM
Well the problem came back and now the SMEC is finally toast :(

Not sure why it went away and then came back but I think I may have found another culprit. We put a MSD Blaster 2 coil on when we first started the project. Just as a "lets try this because nothing else is working" we put a stock coil on and of course the problem went away :banghead:

So now im wondering if the MSD coil needs a ballast resistor??? I searched around and everybody says that you dont need one on a TD but why would this coil be toasting my SMEC? I defective exchanged the MSD coil for a new one at advance auto and im going to see if the new one does the same thing. If the problem is still there I guess ill have to try a ballast resistor.

You mean a capacitor for the coil? It will help keep the spark hot when the coil discharges, but I don't think it's going to fix your problem. Plus, I thought ballast resistors were for alternators, no?

Are you sure that you didn't previously damage the smec so bad that you ensured it's early death? Once you start letting the magic smoke out, there's no way to get it back in :).