ECU A6 only provides signal intermittently.

Hello,

I really hope someone can help me, because I'm starting to feel desperate.
Model: Audi A6 2.5 TDI, manufactured in 1999, AFB engine

Had a tuning chip installed recently, then I got a replacement control unit when I removed it, and it worked quite well.
Now I had a new chip installed (soldered) and it was working perfectly until recently.
A few days ago, I had a problem where my fuel tank ran dry because the fuel pump wasn't working properly -> air in the diesel line.

Now we have located the error: the 4-pin, 10th connector on the control unit is supposedly providing the ground for the activation of the fuel relay, but not always. When starting, it does provide ground, but after a while, nothing comes out. We have temporarily bypassed the relay, and the car is now running.

There could be a few reasons why the mass only comes intermittently. The tuner believes it's not his fault because nothing has been changed, and if a solder joint were the problem, the car wouldn't run at all.

Please help me...
Hi Heli

P.S.: The error log does not show any errors...

Hello,


Actually, these tuners should respond and sort out this mess.
It will also be very difficult to diagnose a ST segment elevation from a distance.

Pin 10 (D) must definitely be connected to ground. (Power supply terminal 86 at the fuel pump.) Relay)

What could it be?

The probability of this happening is relatively high.
This wouldn't be the first time.

It is incorrect to say that it cannot be the STG because it is running, because only a small area of the STG was bypassed by bridging.


Greetings

Mati

Okay, then I'll continue my search in this area, I guess...

Do you perhaps have a wiring diagram (I think that's what it's called) for this control unit, since you know the pinout? Please send it to me at: slmach@gmx.at

1000 thanks, best regards, Heli

Hello,



I unfortunately don't have the wiring diagram for the control unit itself.
My plans end at the exit and entrance of the control device.

Go to the tuner and have him check his work.



Greetings

Mati

Okay, thanks...

P.S.: New insights... This will never result in mass, not as expected - no mass - mass - etc.

He also modified the start button, perhaps because the start button prevents the relay from being activated.

Okay, then,


Good luck!


Greetings


Mati