Hello. The car is a Skoda Fabia 1.6TDI, 75 hp, 55 kW, 2011. The problem is the following:
- A few months ago, when the temperatures were below zero, the hydraulic light came on when the ignition was turned on and the steering wheel stiffened, but while I cleaned the snow from the car, the light went out (I don't remember if it was when the ignition was restarted). Since then there was no problem until 10 days ago. It came on again, however, at an outside temperature of 7°. The plugs and hydraulic fluid are normal. I've had 2 diagnostics at different workshops and they say it's a pump. The pump on the car was TRW 6Q0423156 AB. It was replaced with a Koyo(i think from Audi A2) 8Z0423156 F one/so they say it's Koyo from the store where I bought it/. The problem remained, but the lamp lights up even before ignition - on contact. The steering wheel remain stiffened. Diagnostics now shows error G250 - Power steering sensor. Does this mean the new pump is working? Should the sensor be adapted to the new pump or should a TRW pump be sought/recycled? Is it possible to fix it if I replace the sensor with a Koyo one/if available/? I have read in Russian forums about people who have suffered on the subject and they share the opinion that the pump, rack and sensor must be the same brand. I am attaching 2 photos of the new/second-hand one without sticker/ and one of the sticker on the old one/still installed/. Thanks in advance.

 

 

Yes, the sensor and pump need to be the same brand, the rack is purely a mechanical device and doesn't care which system is fitted.

Koyo system uses hall effect angle sensing; TRW capacitive. Rack, sensor and pump all must match.

Are you sure that replacement doesn't have TRW written on top of the green cap? Koyo has 4-pin angle sensor connector, that looks like a 3-pin?

I think that 8Z0 part is just not a compatible number, what made you think it was?

1 hour ago, Breezy_Pete said:

Are you sure that replacement doesn't have TRW written on top of the green cap? Koyo has 4-pin angle sensor connector, that looks like a 3-pin?

Not sure, but pins are 3 for sure. 

 

1 hour ago, Breezy_Pete said:

I think that 8Z0 part is just not a compatible number, what made you think it was?

On VCDS Vag number of the current pump is 8Z0423156 as I wrote it. 

Yeah, I don't see anywhere that lists 8Z0423156F and 6Q0423156AB as being compatible. I think this Audi part is from a much earlier generation (~2001) so may have a different capacitance sensor, there was a change around 2003 in Fabia Mk1 with racks/sensors from before then not being compatible with later ones, even when both are TRW.

Edited 18 March, 20233 yr by Breezy_Pete
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Are you familiar with coding with VCDS and can you tell me can I do it by myself like this. 

I think that's only coding of the steering weight options, which I have done successfully.

If the hardware isn't compatible, I think it will not help you.

Did the seller of the 8Z0 Audi part tell you that it was compatible with your 6Q0423156AB?

 

 

Audi A2 is 8Z and based on Polo 9N platform the same as the Fabia 1 or 2 so the pump is fine.

Edited 18 March, 20233 yr by sepulchrave

2 hours ago, Breezy_Pete said:

Did the seller of the 8Z0 Audi part tell you that it was compatible with your 6Q0423156AB?

Yes, he did tell me. Actually after swaping the pump nothing has changed. Is it possible the "new" pump is broken or not working?

Yes, that's possible, especially if it is 20+ years old.

I would suggest getting one that is newer than the one you are replacing.

If you message me your VIN I can look up current part number for you. That should enable finding alternative part numbers that are definitely compatible.

 

Hi again. Today I've changed the pump with working one and all problems gone. 
Thank you all! Hope you have a good day! 

Part number of this pump?

Just now, Breezy_Pete said:

Part number of this pump?

Actually it was with the same number - 6Q0423156AB

Perfect, thanks.