AUDI A3 8L, 1.6 Gasoline + LPG: Engine Fails to Start, Suspected ECU Damage

Hello, I have AUDI A3 8L, 1.6 gasoline + LPG.
I am asking you for help, I cannot start the engine.
It started with the fact that for several months every few (naście) days I had problems firing the car. It was enough then that I waited a moment, about 10 to 30 minutes and the car was on fire.

Now I can't fire at all.

Things I checked:
- the fuel pump does not start either when the ignition is switched on or when turning the starter.
- the pump relay (167) works, after applying voltage the 'pyka' relay, the contacts inside the relay are clean.
- after inserting the relay into its place, feel at hand when trying to start the engine that it turns on.
- after applying voltage from the battery directly to the pump, the engine also does not start.
- I can't start the engine, emergency on LPG
- I don't think there is a spark on the cable going to the candle (I'm not sure if I checked it correctly, please give me a hint how to check it carefully).
- I can't connect to the engine module via VCDS, with another module, e.g. ABS, the program connects without a problem, hence the conclusion that the interface and the cable itself are OK.
- and of course I checked the fuses - they are OK.

From what I read on the forum, the ECU driver probably fell.
Please, tell me what else I can check - on Monday I want to check if there is voltage on the plug going to the ECU.
Only now a question for you - I found the plug diagram (in truth to A2, but probably the same link ), is the link post scheme good and applicable to A3? Which means "relay power"
If it turns out that the power supply in the plug is good, does it really mean that the driver is free?
Is the diagram (from the link) sufficient to try to connect the ECU via a cable to the computer?

I am asking for advice, what else can I check?
Thanks in advance for your help, best regards.

Hello, enter the engine code.

sulof1601 wrote:

Hello, enter the engine code.

Engine code: APF

APF has the Simos 33 (Multi Point) driver and in the link you have the description of the Bosch driver. Go to Google and enter Simos 33 pin out.

Did you supply voltage to the fuel pump? This can be done by removing the relay and shorting the appropriate contacts. The pump should then work, if it can't be heard, I would bet on damage to the pump (burned, stuck pump motor).

Added after 13 [minutes]:

The 1.6 APF engine has a Bosch motronic.

jareckim wrote:

Did you supply voltage to the fuel pump? This can be done by removing the relay and shorting the appropriate contacts. The pump should then work, if it can't be heard, I would bet on damage to the pump (burned, stuck pump motor).
Added after 13 [minutes]:
The 1.6 APF engine has a Bosch motronic.

As I wrote at the beginning, the pump works. I connected the pump directly from the battery and it worked.

The driver is SIEMENSA. Code 06A 906 033 A.
Can someone send a description of the pins. I tried, but to no avail.

Here is the diagram ....

Thanks for the diagram.

If I combine well and understand the diagram, then I should definitely have mass on pins 1 and 2.

Correct me if I'm wrong - the numbers in the upper left (30 and 15) and in the lower left corner of the diagram (31) indicate the numbers of pins in the controller, whether these are numbers not associated with it.

Because if so, it means that I should have ground on pin 31, voltage 30 straight from battery, and voltage 15 after turning on the ignition?

In addition, the voltage should appear on pin No. 3 after turning on the relay.
The relay is turned on in turn from pin 23 or 62. So probably on the plug on pin 3 there will be no voltage?

And the last thing I see is that voltage 62 will appear after switching on the ignition.

Please let me know if what I wrote makes sense. If not, write which pins to check.

Thanks again in advance.

It is strange that it is simensa, because according to AutoCom it should be in the APF bosch engine.
The designations 15, 30, 31 do not apply to the controller, they are system designations according to DIN 72552

Battery
15 positive battery supply after switching on the ignition
30 positive power supply directly from the battery
30a plus power supply directly from the second battery via 12/24 V relay
31 minus battery or weight
31a minus the battery directly or ground via a 12/24 V relay
31b minus the battery or weight through the switch
31c minus the battery via a 12/24 V relay

At 62 is given a plus after the ignition switch, and the relay control is from 23 and it is a relay to control the fan and has nothing to do with the lack of firing.

The driver is Siemens, when I get home I will send a picture.

So to sum up - on the plug for the controller on pins 1 and 2 I should have mass, and on pin 62 the voltage after switching on the ignition.
What about pin 3, shouldn't there be voltage after switching on the relay (controlled from pin 23)? When is this relay turned on?

On the other hand, voltage will not go to pin 3 as the controller will be disconnected, as I will check the pins: /

So 1.2 - mass, 62 - voltage?

l1715s wrote:

The driver is Siemens, when I get home I will send a picture.

It does not matter, it is important what is in reality, not in the descriptions. AutoCom says that audi APF engines are motronic, but what is important is what should not be.

l1715s wrote:

So 1.2 - mass, 62 - voltage?

Yes

I checked and the weight is on pins 1,2. There is also 62 voltage on the pin. The car still doesn't smoke. Earlier when it stopped, it fired. I think it's good. What else could I check?

I checked relay 167 once, after shorting the contacts the ammeter shows over 5A, the pump turns on.

On Monday, I think I'll give it to someone wise if I can't find anything.

In the attachment there is a photo of the driver.

In general, a gasoline engine requires fuel, air and a spark to function properly. It also needs a properly functioning timing system. Assuming that everything is ok with the timing gear, you should check if it is so-called spark and whether fuel is supplied. The spark can be checked by unscrewing one candle and after putting it on the pipe and applying to the mass someone must turn off the starter. There is a spark, damage must be sought in the fuel system, none in the ignition system (coil, coils, wires, computer, immobilizer, alarm, ignition cut off, etc.). In the fuel system, it should check whether it supplies fuel at all to the injection rail. Because the sound of a pump does not mean that it is pumping something. To check this, you need to remove the fuel line at the rail, place the container and turn it on with the starter.

That's how I came to check the spark thoroughly, because I'm not sure of the previous check. I'll do it later.

Is it possible that if the voltage is where it should be after switching on the ignition, then the ignition block may be damaged?

Finally power this controller and see if there is communication
What do you have on the third pin?

Hi,
Buddy, you managed to overcome this bug with firing, because I have the same problem ....

icpawel79 wrote:

Buddy, you managed to overcome this problem with firing, because I have the same problem ...

Probably the answer after such a long time will be of no use to you, but I will leave for posterity.
Maybe someone will be useful and help something.

The problem was caused by damaged relay no. 30, located under the hood, near the battery.
I bought a replacement for PLN 20 and I still fly without problems today.

Hi, I was overtaken by an electro mechanic, the problem was the relay under the hood, cold solder ...