Fans running constantly, Various Fault Codes

[DazJ]

Hi All,

Just wondering if anyone could shed any light on a fault.
When starting the engine the fans start running and continue to run until the engine is stopped.
The only faults stored are below
5262 - Exhaust Pressure Sensor 1 (G450)
P0472 00 [039] - Signal too Low
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 235139 km
Date: 2015.03.28
Time: 19:06:53
00256 - A/C Pressure/Temperature Sensor (G395)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 3
Fault Frequency: 1
Reset counter: 48
Mileage: 235139 km
Time Indication: 0
Date: 2015.03.28
Time: 19:06:58

[Rob69]

Reckon your g395 ac switch is causing fan to run. I think there was an audi tsb issued on these switches.

[dan2485]

What engine and Year?

For the G450 fault check that the wiring to the sensor is Ok, It could be a Hole in the exhaust or it could be the sensor or ECU.

[DazJ]

Thank you, I didn't want to replace the sensor if it was going to be something different. Will try this and see what happens.
Is the G395 sensor - 4H0959126?

Its a 2010 - 2.0TDie SE.

[dan2485]

The DPF sensor on your car is at fault for the G450 error, now that you posted up an engine code I had the same issue on a friends 2010 2.0 Le Mans back in January 2014.



5262 - Exhaust Pressure Sensor 1 (G450)
P0472 00 [032] - Signal too Low
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 4
Mileage: 191313 km
Date: 2014.01.19
Time: 06:36:33

The Sensor (059 906 051 A) back then cost £60 from TPS.

It takes around 20 minutes to change as you will need to remove the Fuel filter holder to gain better access to the hose pipe clips.

Also get a can of compressed air if you don't have a compressor to blow back hoses before fitting the new sensor, then you need do an adaptation using VCDS once fitted.

Google SSP 420 for your engine.

The G395 sensor can be 4F0 959 126 C for up to 01/2010 and 4H0 959 126 for after 01/2010.

[DazJ]

Hi Dan,

The engine code shown by VCDS is (SK10YPC - Engine (J623-CAGB)), don't know if you could get the sensor part number for this?

[dan2485]

They are the same sensor (g450).
The sensor number is posted above.
Known for giving trouble.

[claudiur]

This sensor is Temperature sensor before turbocharger? i have there on it a temperature of 849.6C with cold engine. i think its down, and my fans also work permanently

[DazJ]

The fan problem we had cured after replacing the sensor.

[claudiur]

You have a photos of this sensor?