DIYPNP NA6 unsolved issue
 

HI All.
I have searched and searched and searched, had help from various people back on MX5CARTALK over here in Aus.
Still no luck

My issue is this,
I received my Braineack DIYPNP, on hooking it up it connected to my laptop just fine.
Car would not start but that was solved with a quick REQ fuel issue.
It worked that day.
The very next day the car did nothing.
I could not connect to the MS, nothing was happening.

I noticed that on the first day, i could hear fuel running in the engine bay through the rail when ever the ignition was on.
Now i hear nothing.
A friends NA6 with a Braineack DIYPNP has this fuel running noise too so that must be normal.
So i assume something has gone bad.

I sent the MS to our resident Expert who tested it on a bench and said it all seems good.
If i use a 12v wall adaptor the unit powers up and connects to my laptop perfectly. So i agree with him.
If i suck and blow on a vacuum hose (yes odd i know :giggle:), Tunerstudios reacts to this input.
As soon as it touches my cars harness, DEAD.

I tried the unit in my brothers NA6 to make sure it was not my car. Same thing. DEAD.

I have tested my harness in my car and am getting 12v, which should have been obvious by the fact my stock ecu runs perfectly.

I have pulled the MS out of its box and tested in the car and i am getting 12v on the lower edge of the main board, i am also getting 5v from the 5v next to the 12v.

When i use the 12v wall adaptor i get 12v for a about 2 seconds up top for the fuel pump then it drops to 0v as i believe it should.
When the MS is in my car i only get 5v there and only for a quarter of a second. Like a flash.


Does anyone have any further ideas??
i would be ever appreciative.

Something in the harness must be shorting or gnding out something. So even though you get 12v and 5v on the MS2 you still can't connect via serial yeah? Then something else in the car is pulling down something (that somehow doesn't bother the stock ecu) and this must be killing the MS. Weird for sure.

Try and disconnect as much as you can... the igniter, the fuel injectors, even the fuel pump... as much as possible to try and figure out what is causing the MS2 to gnd out and die. If it works on 12V on a pack then the only thing left is something on the harness that is gnd'ing out.

G

So, you mean disconnect the actual devices from the engine bay??

I kind of do not think this is the issue as the MS does not work on a separate NA6.
2 Cars shorting out would be a little odd surely??

I think there is an issue with the ECU.

It is driving me actually insane :vash:
How can it work on 12v from the wall yet not on different cars harnesses.

I almost wish it worked on the other car, that way i would know the issue was with my car and that could be more easily rectified.

Nope. Leave connected to harness but remove anything you can think of that might be running off the ECU - try and eliminate anything that can be bringing the unit down - for example (things I'm thinking of) is TPS - is it stock? If stock, then you MUST have it removed or it won't work - in fact it could be culprit in fact.

G

Your a genius!!! :bowrofl:

It was in fact the stock TPS still connected.. i feel so dumb. :noob:

The first time i used the MS i disconnected it and then when i went back to stock i reconnected it.
I just stupidly forgot to disconnect it and it was grounding the MS out.

As soon as i disconnected it i heard the fuel pump operate correctly and it connected to TunerStudios!!

Glad that fixed it...l was really starting to wonder as I'm sure I tested it fine!

I would strongly suggest you get a VTPS as megasquirt is a bitch to get to idle without a TPS. Plus EA isn't fun running solely on MAP...

G