Power Issues/Seems to be related to ESP/ABS -- Audi s4

[m.s4]

So recently I have been experiencing some really weird symptoms in my car with my HFS-3.

Any time I get the ESP to turn on, or get substantial wheel-spin with ESP off the power flashes. The gauge goes dim except for the yellow water level light.

-Grounds are separated
-All wires have been double checked for proper placement
-water level sensor is unplugged

I didn't have these issues in the dry (lots of snow in MN since nov).
It also does it if i have the system off. The yellow light will come on.

It doesn't happen if I unplug my abs/esp fuse. I am investigating the problem being my car's wiring, but thought I would post here for some insight.

Thanks,
Mark

[Richard L]

This problem has mde easier for me as you have given me some clues.

If the gauge goes dim, it is due to the main power supply into the system, ie, the red wire from the 4-way power plug. As the yellow led's supply is regulated to 5V internally it will not be affected by a noisy 12V supply.

Is it possible to find another loaction for the red wire (molex)? It can be connected directly to the battery. The system's will not drain power until the ignition swicth is at the "run" position.

[m.s4]

This problem has mde easier for me as you have given me some clues.

If the gauge goes dim, it is due to the main power supply into the system, ie, the red wire from the 4-way power plug. As the yellow led's supply is regulated to 5V internally it will not be affected by a noisy 12V supply.

Is it possible to find another loaction for the red wire (molex)? It can be connected directly to the battery. The system's will not drain power until the ignition swicth is at the "run" position.

I will run it directly to the battery and see.
It goes to the same terminal as the other red ignition wire from the "Ecu" wires.

Would this cause the yellow light to come on when the entire system is off. (Blank gauge, then only the yellow light comes on even the the whole system is turned off.)?

[Richard L]

The main supply tio the system is from the molex connector. The other red wire (yellow harness) merely power on an onboard relay and let the main power into the system.

This red wire (yellow harness) is not prone to noise.

[m.s4]

So I ended up relocating the main power wire directly to the battery and the issue went away for a little bit. It's snowing here and the problem is back.

As soon as ESP activates the gauge flashes leaving the yellow light on when the rest of the lights go out. Does it less with ESP switched off but still does it if you whip around a turn and get wheelspin.

Seems that if I take out the ABS/ESP fuses the whole problem goes away, obviously leaving me without ESP/ABS.

My question now is, Is this power to the system related or is it Signal (IDC) related?

Also: New battery and did an alternator test and everything checks out fine.

Mark

[m.s4]

Update: unplugged a chinese made phone charge I had plugged in and the problem is a lot less consistent but still present.

[Richard L]

This is getting very interesting. I wonder if I send you another conrtroller it may not improve the situation.

We have a similar issue earlier with the gauge cable. I wonder if you can unplug and examine the wire ends, if any one of the stranded copper wire are close to touching each other occasionally.

From your description it appear to be a electrical noise problem. I like to send you an line noise suppressor and see if it helps. Ity is the first time we have this type of interference. Please pm me your address again.

[m.s4]

PM'd

I've checked the connections, all the non-used wires are separated and electrical taped.
All the other connections are soldered.

Thanks,
Mark

[m.s4]

Tried a new MAF today, still does it. It wil occasionally cut out at high rpms so I was trying to rul that out.

This indicates a loss of power to the aquamist, correct? Or should I be looking for something on my vehicle that is causing fuel cut and messing with IDC signal?

[Richard L]

I wonder if you can wiring the red wire of the grey connector directly to the igniton key switch (run of pre-crank position). Make sure it has a full 12V.

This inteference is so strange.

Is the s4 a FSi (direct injection system)? I think it is just a conventional injection system.

[m.s4]

I wonder if you can wiring the red wire of the grey connector directly to the igniton key switch (run of pre-crank position). Make sure it has a full 12V.

This inteference is so strange.

Is the s4 a FSi (direct injection system)? I think it is just a conventional injection system.


It's already wired to the ignition switch.

it's not FSI. I have it tapped into a fuel injector wire.

[m.s4]

Richard,
I have both power wires going directly to the batter with a switch in between the smaller power wire that comes from the ecu harness.

If I turn the car on then power up the aquamist everything turns on normally, then when I turn the car off (if I don't turn off the aquamist first) as soon as the car is off the pump starts running (is this normal?)

Also, If i have the car off and start the system directly from the battery, once it is booted up the pump runs (gauge lit and bars flowing).

Is my controller bad?

Regards,
Mark

[Richard L]

Do not start the system until the kety switch is on the pre-crank position. If the system is switched on (battery power), the system will spray fully will flood your engine.

This is becuase if there is no 12V power to the fuel injector, the system will mistakenly think the injector is at 100% duty cycle and start o inejct.
Only manually start the system after the enigne is running.

When the system was powered from the battery, did you still have flickering problems?

[m.s4]

Do not start the system until the kety switch is on the pre-crank position. If the system is switched on (battery power), the system will spray fully will flood your engine.

This is becuase if there is no 12V power to the fuel injector, the system will mistakenly think the injector is at 100% duty cycle and start o inejct.
Only manually start the system after the enigne is running.

When the system was powered from the battery, did you still have flickering problems?


Snowing pretty heavily, but I didn't on the way home tonight.

I will see more tomorrow.

[Richard L]

Please remind me, which part of the world are you located?

[m.s4]

Please remind me, which part of the world are you located?

Minnesota, USA

Acted up this morning with everything hooked directly to the battery, not sure where to turn now.

[Richard L]

I am wonder if the unit is subject to smal mosture condensation on the circuit board. Please pm me youir address and I like to send you another controller and see if it behaved the same.

During this time, can you rap up the unit or put it in a plactic bag and let me know if it improves.

Richard

[m.s4]

PM Sent,

The controller is inside though, in the dash on the driver side.

When I get wheelspin I'm seeing a slight dip in volts but nothing under 13-13.4v.