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Re: injector drivers on 3x board keep dieing.

Posted: Tue Nov 29, 2011 11:35 am
by Peter Florance
when I overheated mine, you could see where the solder reflowed and the part label was discolored.

Re: injector drivers on 3x board keep dieing.

Posted: Tue Nov 29, 2011 11:47 am
by shaodome
Peter Florance wrote:when I overheated mine, you could see where the solder reflowed and the part label was discolored.
none of mine show any signs like that on ANY of the 3x boards.

Re: injector drivers on 3x board keep dieing.

Posted: Tue Nov 29, 2011 12:52 pm
by shaodome
No word from Bruce? Being that a lot of my customers are 2JZ/1JZ powered vehicles and I have a good amount of them running on the street daily using injectors shown above, this is a pretty big concern for my overall business.

If it is as simple as running some big inline resistors to protect it from happening, I'm good with that. I just want a reliable fix :mrgreen:

Re: injector drivers on 3x board keep dieing.

Posted: Tue Nov 29, 2011 1:57 pm
by jsmcortina
Unsure if this is related or not (just brainstorming) but could you describe exactly your grounding ?
i.e. how many ground wires on the main plug, how many on the MS3X plug. Are the commoned? Where they route and end up.

James

Re: injector drivers on 3x board keep dieing.

Posted: Tue Nov 29, 2011 8:44 pm
by shaodome
On the main PCB for the 3.57 I have 3 18g grounds going to a bolt on the engine block. On the 3x I have all 5 ground pins on 18g wire going to the same ground bolt.

On one of the cars i used a chassis ground near the oem ecu and still had this problem.

Re: injector drivers on 3x board keep dieing.

Posted: Wed Nov 30, 2011 1:07 am
by subwoofer
After reading the data sheet thoroughly, I can only find one weakness in the protective circuits of the VND5N07. If the block diagram is correct, the overvoltage clamp is still active even if the FET is in thermal shutdown, so a prolonged overvoltage condition could severely overheat it. On the other hand, FETs usually have no problem with 175C for shorter periods, and may actually work for surprisingly long at 200C. The energy from a single flyback pulse while in thermal shutdown shouldn't do any permanent damage.

Vin (control pin) is max 18V, could that have been exceeded due to a noisy ground or a ground loop?

Re: injector drivers on 3x board keep dieing.

Posted: Wed Nov 30, 2011 5:16 am
by Peter Florance
shaodome wrote:
Peter Florance wrote:when I overheated mine, you could see where the solder reflowed and the part label was discolored.
none of mine show any signs like that on ANY of the 3x boards.
Then I doubt it is thermal related.

Can you scope gate lead in test mode?

Re: injector drivers on 3x board keep dieing.

Posted: Wed Nov 30, 2011 5:34 am
by shaodome
Peter Florance wrote:
shaodome wrote:
Peter Florance wrote:when I overheated mine, you could see where the solder reflowed and the part label was discolored.
none of mine show any signs like that on ANY of the 3x boards.
Then I doubt it is thermal related.

Can you scope gate lead in test mode?
I think so....

Remember though, the gate lead is now connected to the transistor on channel G and patched back over to the channel A pin to get the car up and running again. So that part is working.

Re: injector drivers on 3x board keep dieing.

Posted: Wed Nov 30, 2011 6:29 am
by Peter Florance
shaodome wrote:
Peter Florance wrote:
shaodome wrote:
none of mine show any signs like that on ANY of the 3x boards.
Then I doubt it is thermal related.

Can you scope gate lead in test mode?
I think so....

Remember though, the gate lead is now connected to the transistor on channel G and patched back over to the channel A pin to get the car up and running again. So that part is working.
I just want to look for any ringing or undershoot. You'll want a 10X probe for sure; otherwise the capacitance in the probe cable may hide the ringing or change the waveform.

Re: injector drivers on 3x board keep dieing.

Posted: Thu Dec 01, 2011 1:00 pm
by shaodome
The scope I thought I could use apparently is broken.....and what you are asking for is a little beyond my current level of understanding. :-/

Any word from Bruce on this?

Re: injector drivers on 3x board keep dieing.

Posted: Thu Dec 01, 2011 1:05 pm
by jsmcortina
Bruce is looking into it.

James

Re: injector drivers on 3x board keep dieing.

Posted: Thu Dec 01, 2011 1:07 pm
by shaodome
jsmcortina wrote:Bruce is looking into it.

James
If he would like one of the failed boards to look it over, I would happily mail it. Just let me know.

Re: injector drivers on 3x board keep dieing.

Posted: Mon Dec 05, 2011 11:08 am
by shaodome
still nothing from bruce?

Re: injector drivers on 3x board keep dieing.

Posted: Mon Dec 05, 2011 3:08 pm
by BCM
Early this past summer I had an injector driver on my MS3X die. I tested on the JimStim and then by the time the car was running it had crapped out. Replaced the MS3X and haven't had it happen again, but it's a race car and I had engine issues middle of the year, so it didn't see a ton of use.

Injectors are from a Volvo 850 Turbo (Orange Tops) - Bosch p/n: 0 280 150 785 high impedence 305cc/min. @ 3BAR fuel pressure 354cc/min. @ 4BAR fuel pressure.

So, I guess I'm curious too in case it happens again. I still do have the failed MS3X somewhere.

Re: injector drivers on 3x board keep dieing.

Posted: Tue Dec 06, 2011 8:09 am
by Matt Cramer
shaodome wrote:still nothing from bruce?
He was on the road attending the MegaMeet. We will be sending your board back to him this week, and we're implementing new testing procedures for the MS3X boards to see if they got a bad batch of the drivers.

Re: injector drivers on 3x board keep dieing.

Posted: Tue Dec 06, 2011 9:16 am
by shaodome
Matt Cramer wrote:
shaodome wrote:still nothing from bruce?
He was on the road attending the MegaMeet. We will be sending your board back to him this week, and we're implementing new testing procedures for the MS3X boards to see if they got a bad batch of the drivers.
Hey Matt,

How was PRI? I just saw Ben's e-mail and I'll have them out to you tonight via priority mail.

Re: injector drivers on 3x board keep dieing.

Posted: Tue Dec 06, 2011 10:40 am
by Matt Cramer
It was a lot of work, but it went great! We've got a page with some photos up here:

http://www.diyautotune.com/events/pri_2 ... _show.html

Re: injector drivers on 3x board keep dieing.

Posted: Sun Jan 08, 2012 5:27 am
by ranster
Probably same fault here.

Been running the Main board injector drivers without issues for few years already (MS2 then upgraded to MS3 daughter board).
2 weeks ago i switched to MS3x (the original batch of 50) to run fully sequential and since then I'm having issues with starting when the car is warm, car hesitates when running up the RPM and is not really drivable. Switching back to the main board drivers (semi-seq) solves it.

I'm using Lucas 440cc high imp injectors (Coil Resistance: 15.9 Ohms)

Any news with this issue?

Re: injector drivers on 3x board keep dieing.

Posted: Sun Jan 08, 2012 8:15 am
by BCM
Ranster - did you test the drivers? When it happened to me I was able to use test mode and show definitively that one was dead...

Re: injector drivers on 3x board keep dieing.

Posted: Sun Jan 08, 2012 8:22 am
by ranster
BCM wrote:Ranster - did you test the drivers? When it happened to me I was able to use test mode and show definitively that one was dead...
Not yet.
I am going to replace the MS3X card today and see how it goes.
Next step will be to test the drivers as you mentioned.