PCB v3.0 mods

[Piledriver]

thx for you patients Pile.

To confirm for the TACH circuit , make sure these are all done (I'm not running an IAC valve):

a) JS0 to IAC1A
b) JS1 to IAC1B
c) JS2 to IAC2A
d) JS3 to IAC2B
e) JS9(+12V) to S12C

Then I can tap into these outputs IAC1A, IAC1B, IAC2A, IAC2B provide a 0-12V signal ?

... Only one line is needed for tach, and unless you are actually driving a stepper motor, there are only two signals each with a complementary output... IAC1 and IAC2.
Example: IAC1 (A,B) A&B will ALWAYS be opposite of each other. Same for IAC2.(processor outputs)
Use IAC1A for tach and pull the rest of the IAC jumpers and you have 3 spare pins on the DB37.

[panel]

Ah man , I thought I had to run those four jumpers even if I wasn't running the IAC. Crap! Still run this jumper though......JS9(+12V) to S12C ?

[Piledriver]

Ah man , I thought I had to run those four jumpers even if I wasn't running the IAC. Crap! Still run this jumper though......JS9(+12V) to S12C ?

If you plan to use any of the IAC outputs, yes.
Don't hook it up if you are NOT using any of the IAC processor pins.
They can drive high or pull low, unlike any other MS output.

Remember--- There are only two "signals", the processor A/B outputs on IAC1/2 are complementary, if A is high, B is low.

[panel]

Guys , have a look here to see if she's all good.

Logic 'spark' output: use the top of R26 output from the MS-2 CPU as the input into TC4427 circuit and the output routes to SPR3 which sends the signal out to the DB37 on pin 5 .Then use pin 5 on the DB37 to send the signal into the coil.

I'd do the same thing for the other circuit but use top of R29 and pin 6 (SPR 4) on the DB37

Fan output: Use the top of R27 output from the MS-2 CPU as the input into the circuit (telling it when to switch on/off) and the output routes to SPR1 which sends the signal out to the DB37 on pin3 .Then use pin3 on the DB37 to control my relay which controls my electronic fan.

Pic as an example :

https://www.diyautotune.com/wp-content ... xample.jpg

Tach output: use pin 25 from the DB37 which internally is from IAC1A.

[Piledriver]

What coils are you driving?
The "LED" circuits only need a pullup resistor to drive LS2 coils or the common cheap VW 4 towers,which are commonly referred to as "IGN4A"s by certain peoples kids and sold for more than the VW dealer charges to the innocent.
They can be had for $35-45 new, coil for a 2000 VW beetle 4 cylinder. AKA VW-106B (or later suffixes)
latest vw part# is 032905106E
http://www.msextra.com/forums/viewtopic ... 01&t=54862

Also see http://www.msextra.com/forums/viewtopic.php?p=441301 don't confuse the VW cop info with the 106B info.
The VW-106B//E only needs the pullups changed per that post.

The only coils AFAIK that require the TCx drivers are the VW cops, that require more + current than a pullup can safely provide. As the VW COPs have a very, VERY long history of suck, I wouldn't suggest those unless you absolutely have to use them for some reason.

I keep hearing they are fixed from rev such and such but still seem to drop like flies @<30K.
...almost have to change them as often as some plugs.

I have also heard (reasonably believable) tales that excessive plug gap from folks running the same plugs forever is what really kills the VW cops, although that doesn't really say much for their durability.

I guess it won't hurt anything if you already have the drivers... but you still may need a pullup to drive the driver, just so there is a signal.

[panel]

LS2

What coils are you driving?

[ps2375]

So, I'm helping a friend with his V3.0PCB install. He's using the 106E coil on my recommendation based upon this thread. I want to trigger from D14 & D19 -ve, would I be correct in using a 1K resistor to the 12V on Proto Area w/ MS set for Going Low? From the links in this thread and others it is linked to, it appears that 12V works better and since the coil has a built-in driver, the high current transistors are not really needed. And I may add the 330 R in series as the person in the linked to thread did.

[ps2375]

Modded the board with the 1K resistors and the 330 ohm in series, and it fired right up after getting a couple of pops out of it. Swapped the lead pairs and fired on first rotation! Easiest first start I've ever had.

[panel]

Right on! It's a good feeling!

[ToRy 70]

Hi gents,

Don't mean to butt in but this is the most recent post involving the 106E/106B coil, and Pile seems familiar. Could you gents review my thread here?

viewtopic.php?f=63&t=149907

I need some help in assembling plug wires to work with this coil. Thanks!

[Piledriver]

posted there.