Audi A3 Sportback - Esp warning light on

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Thu 25 Jun 2015 22:56
Audi A3 Sportback - Esp warning light on - mak

Audi A3 8PA 2005my

Esp warning light is on and diagnosis with VCDS shows fault 00493-ESP-Sensor unit (G419): No signal/Communication. I have tried replacing the sensor unit with a refurbished one (10 year guarantee?) as the dealers wanted over £700 for one. Light still on so firm sent another one, still no joy. Not sure if it is the sensor unit as could also be wiring or connectors from brake electronics, abs unit, to esp sensor. Has anybody had this problem and if so how did they resolve it. Many thanks in anticipation.

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Thu 25 Jun 2015 23:48
Audi A3 Sportback - Esp warning light on - elekie&a/c doctor

Not too sure what part you have replaced,but the G419 is the steering angle sensor that sits behind the steering wheel and measures steering angle and rate of rotation.All part of the esp system

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Fri 26 Jun 2015 14:49
Audi A3 Sportback - Esp warning light on - dieselnut

This is from the Ross Tech site :-

wiki.ross-tech.com/wiki/index.php/00493

It looks like it is the G419 unit that is faulty rather than the G85 sensor.

Once fitted, I think the G419 will need to be adapted to the car using the VCDS cable & software.

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Fri 26 Jun 2015 16:55
Audi A3 Sportback - Esp warning light on - mak

Many thanks for the replies.

The Audi Workshop Manuals refers to the sensor unit (G419) as being underneath the right hand seat and it's this that was replaced. The ESP sensor contains the following senders: lateral acceleration sender-G200, yaw rate sender-G202 and longitude acceleration sender-G251 (only for 4 wheel drive vehicles). After fitting the VCDS couldn't communicate with the unit as tried to calibrate the lateral acceleration sender G200 within the unit. As already said I replaced the original unit with refurbished units instead of new to save cost perhaps could try second hand unit but no way of telling if they work. Just worried it may be the connectionsor wiring fault. Does anybody know where the ESP control unit is?

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Fri 26 Jun 2015 17:15
Audi A3 Sportback - Esp warning light on - elekie&a/c doctor
The esp control unit is part of the abs ecu
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Sat 27 Jun 2015 09:00
Audi A3 Sportback - Esp warning light on - chris.o
Can you disable ESP with VCDS? I seem to remember Having trouble with a Passat ESP light.
Think I used VCDS to basically tell car it wasn't fitted with it. The ABS continued to work as intended.

Chris.
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Sat 27 Jun 2015 09:01
Audi A3 Sportback - Esp warning light on - mak

As there are two possible faults, sensor unit or connectors/wiring I felt it was best to eliminate the sensor so that is why I used the less expensive refurbished units. No way of knowing if they were in working order. Does anybody know how I could test the sensor unit to see if it is working, the original is back in the car? If this is the problem then I will replace with OEM and save time/expense testing connectors/wiring.

Just to let you know, the ESP warning light first came on during a journey and stayed on for the rest of the day. The next day it was on first thing but during the day went out upon starting and stayed out for about 1/2 mile then came back on. It has stayed on ever since. Does this indicate anything?

Many thanks for your help.

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Sun 28 Jun 2015 16:30
Audi A3 Sportback - Esp warning light on - dieselnut

The original problem was " Sensor unit (G419): No signal/Communication " & is still the same after several second hand units fitted.

I would have expected "No Communication" means that VCDS is unable to talk to the unit, & it would be unreasonable to expect the other 2 units to be completely duff as well. Perhaps eleki can confirm that.

The unit will need power & the communication wires to be intact for it to communicate with VCDS. I would be checking out the wiring to make sure all is ok there.

Also A3's, in common with A4's & Passats of this ilk suffer with water ingress problems from the pollen filter housing & plenum chamber into the passenger & driver side footwells.There is often no sign of water until you lift the carpets & thick underfoam.

This can play havoc with the wiring, earth out circuits & cause wires to break off in connectors etc.

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Sun 28 Jun 2015 19:21
Audi A3 Sportback - Esp warning light on - elekie&a/c doctor

As above,no comms means either power/earth supply problem,fault with unit,or wiring to it.You need to pin out the wiring from the G419 (lateral /yaw rate sensor) back to the abs/esp ecu.Seem to have misread the op and is not the sterring angle sensor.However it may be an idea to read the actual value live data of this to make sure it is working ok

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Mon 29 Jun 2015 09:08
Audi A3 Sportback - Esp warning light on - Railroad.
No communication can also mean that the ESP unit is not communicating with other controllers. Check the installation list in the Gateway module with VCDS to see if the checkbox next to it is ticked. It could also have a broken CAN wire somewhere, but locating these things is often quite difficult.
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Mon 29 Jun 2015 12:43
Audi A3 Sportback - Esp warning light on - mak

Many, many thanks for all your replies.

The steering angle is within limits.

Worried that it may be a wiring/connector issue which sounds expensive but as I mentioned earlier on how it first happened just not 100% sure.

Just to let you know, the ESP warning light first came on during a journey and stayed on for the rest of the day. The next day it was on first thing but during the day went out upon starting and stayed out for about 1/2 mile then came back on. It has stayed on ever since.

Does this sound like a bad connection/broken wire to you?

Best regards

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