A6 2.4 runs for 10 seconds and then dies.

I have an A6 that runs for about 10 seconds and then dies, and the cooling fan starts running.

After that, you can no longer access the engine control unit with VCDS. Gateway Motor 0

Measured the power supply terminal 30 on the control unit (B3, B4, B6).
Clamp 30 to B92 (from circuit breaker in the water box)
Clamp 15 has voltage present on B87 everywhere.

If he stands for a longer period, then you have to go back into the engine control unit.
The car then starts, runs for a few seconds, and then dies again.

I connected a lamp to terminal B3, but the lamp is lit, and the motor is dead.

This happened twice, and then the fuel pump relay started switching on. The engine is no longer starting.

Pump relay shorted, but motor still not running.
The lamp at B3 is still lit, but after several attempts, I am no longer able to access the engine control unit, and in the gateway, I have a 0 for the engine. The lamp at B3 is no longer lit, but the lamps at connections B92 and B87 are. Fan motor running

I also briefly short-circuited the voltage regulator relay and the fuel pump relay, but that doesn't work either.

Therefore, the engine control unit no longer controls the voltage supply relay for terminal 30 after a certain period of time.

My question: Does the control unit, at terminals B92 (terminal 30) and B87 (terminal 15), and of course the three ground connections (B1, B2, B4), provide a ground connection to the power supply relay (terminal 30) so that it can then function correctly?

I can't reach the starter lock solenoid, but as far as I remember, it's integrated into the 05 model.


Here are a few MWB

Address 05: Access/Start Report (4F0 910 852)

15:18:21 Block 007: Voltages
12.960 V Supply Voltage
0.288 V Output Voltage to activate Term. 15 Here, nothing is ever displayed
0.288 V Output Voltage to activate Term. 75X. I have 10.8V here at startup.
0.000 V Output Voltage to activate Term. 50. When starting, I have 10.8 V here

15:20:08 Block 008: Ignition Switch (E415)

unactivated Locked 1
activated Locked 2
activated Unlocked

15:21:29 Block 009
Unused Switch Motor 1 Relay 1 Term. 15
Operates Switch Motor 2 Relay 2 Term. 15
a K15/P Wire from Ignition Sw. (E415) When ignition is off, set to on
from K15/S Wire from Ignition Sw. (E415) Always OFF

Should the MWB 007/7 specify the battery voltage during starting? And what about MWB 009/4?

Address 09: Central Electrical (4F0 910 279 K)

15:25:11 Block 015: Clamping Status
a clamp 15
a clamp X
from clamp 50
n.v.

Address 4F: Central Electrical II (4F0 910 280)

15:26:13 Block 005: Power Supply
a clamp 15 status
a Klemme X Status
0.1 Dynamic Battery Management System Shutdown Level
0.1 Static Battery Controller Shutdown Level

Could now measure the CAN connections with an oscilloscope. But I only have an old, analog one.

Just measured at the power supply relay terminal 30, no ground from the control unit, and the car won't start. Voltage present at terminals B87 and B94.

I once had a T4, and after starting, the engine control unit (ECU) would malfunction, causing the engine to repeatedly shut down. Sounds a bit similar to me.

Hello everyone!

According to the car scan, some StGe (presumably referring to something specific) are experiencing overvoltage, up to the end of the (m. W.) Measurement range of 15.5V.
Was wurde hier möglicherweise verwendet, um das Problem zu beheben, als die Starterbatterie leer war, während man versuchte, das Auto zu starten, z. B. ein Schnellader? Oder liegt möglicherweise tatsächlich ein Fehler vor, wie auch im Autoscanner angegeben, am Generator?

As the next step, I would now measure the voltages again using a good (!) digital multimeter, including. Check Min-Max recording against MStG.
Should there actually be a {VOLTAGE} in the {BOARD NETWORK}, then various... StGe activate self-protection mode. ...however, the MStG should also be able to store this in memory.

Best regards from Munich!

klahaui wrote:

I once had a T4, and after starting, the engine control unit malfunctioned, and the engine kept cutting out. Sounds a bit similar to me.

And what was the mistake?

DieselBär30x wrote:

Hello everyone! According to Autoscan, some STG (Sub-Transistor Gate) overvoltages are being reported, specifically up to the end of the (m. W.) Measurement range of 15.5V. Was wurde hier möglicherweise verwendet, um das Problem zu beheben, als die Starterbatterie leer war, während man versuchte, das Auto mit einem Schnellader zu starten? Oder liegt das Problem möglicherweise tatsächlich am Generator, wie auch im Autoscan aufgeführt? As the next step, I would now measure the voltages again using a good (!) digital multimeter, including. Check Min-Max recording against MStG. Should there actually be a {VOLTAGE} in the {BOARD NETWORK}, then various... StGe activate self-protection mode. ...however, the MStG should also be able to store this in memory. Best regards from Munich!

This is possible with a quick charger or starter charger. I have repeatedly had starting problems due to my driving style (2-3 km, then standing for a whole day and then another 2-3 km) and a problem with the power supply until the MMI update. Generator must be checked when it starts running again.

ECU placed in the house overnight. Then I connected it to the table, but without the gateway, I couldn't access it with VCDS. I measured at the CAN connections, here I had 2.4V on L and 2.6V on H (120 Ohms). Then, when measuring with an EDC17, the values were L 2.0V and H 2.9V (127Ohm)

I reinstalled it in the car, but it was no longer accessible in the car scan. Then I carefully examined the measurement blocks in the 2005 model again (I now have more information about the MWB7), and then I cleared all the errors, and suddenly the engine control unit is back. Started immediately and has been running for over 2 hours in the LL.

Is it possible that the engine control unit "detached" and then reset itself after a longer disconnection from the car's electrical system???

Had this issue on a van, but here, I could only see the errors, not delete them.

However, I will leave it in the cold overnight and try again.

Hi,

Access via CAN must function with the engine control unit, correct pins must be identified and L/H must not be swapped?

Otherwise, I suspect that the engine control unit is malfunctioning and causing it to run intermittently. I wouldn't install it in this case, as the car might initially start driving again, but potentially fail to start at the most inappropriate time and in the most ridiculous situations...

Best regards, Rainer

B67 CAN-L
B68 CAN-H
B1 Mass
B3, B87, B92 Voltage