2 hours ago, Daddyfixitsnew1 said:

once the sensor & new pump are fitted....will they need diagnostics to code/pair them up to each other ?

 

 

No, plug and play.

Hello gents;

The car has been done, it needed the pump and the steering sensor that was faulty, but then ended up with communication problem between the  pump/sensor so it was taken to an independent VW-Audi tech 

who is renowned for his VCDS & diag work, It was down to a software issue ?      So its back home and getting its annual service next weekend, plus i want a set of front mudflaps to put on it before the snow/grit season arrives.

I'll try to research this a bit, cos I'm not 100% sure, but I wouldn't expect the signal that's coming from the turn rate sensor to be 'communication' as such.

It might be though.  

I'll start with wiring diagrams to see how the connections are labelled, then the relevant SSP.

Wiring diagram doesn't help.

SSP doesn't add much to my understanding about what comes out of the sensor except that it claims to send angle as well as turn rate info, where I thought it was only the latter.  

 

It says this:

The power steering sensor G250 is located at
the top in the steering gear and surrounds the
input shaft of the steering gear. It detects the
steering wheel angle and computes the
steering angle rate. It is not an absolute angle
sensor (steering wheel angle proportional to
steering wheel lock)!

 

Later it shows a diagram of the capacitive sensor:

 

I guess, looking at that it can tell angle by which of the 9 plates in the semi-circle on the left are covered by rotor, given an initial lock-to-lock calibration or something,   

Was any such calibration done by you after installation?

 

TRW systems use the above capacitive sensing technology, Koyo systems use completely different hall effect technology.

 

Was the pump brand new? (Where from?) 

 

Good to hear you're up and running anyway.

 

Edited 28 November, 20205 yr by Wino

G250 has always had an intermittent fault since i got car over a year ago;  

 

car was done at mates garage as i am on crutches at the minute.

 

pump was a TRW unit from Euro, it was when it started up and worked for a bit...then it packed in on road test

 

trying to communicate with snap on  scanner it could not locate controller (pump) so it went to a 2nd tech who is ****-hot VW-Audi and he uses VCDS  & dealer level kit

apparently there was a coding issue with pump that meant wiping controller (pump)

 

I got a brand new G250 from ebay from Carlisle in the meantime---as it had the intermittent fault anyway

 

I was always under the impression it was a plug & play unit, do the lock to lock thing and drive it above 20mph dressed as santa !!!  but the car proved it to be otherwise.......

Edited 28 November, 20205 yr by Daddyfixitsnew1
fixed 1st line

I misunderstood your previous post, thinking that it was referring to a communication problem between G250 sensor and PAS module.  Now you've clarified it that it was between module and 'car' I'm less perplexed. Cheers.

 

I still don't know for sure what comes out of the G250 sensor, cos although it appears to be able to infer the steering wheel position/angle, I'm not sure why it would need to.  Possibly something lost/added in translation from the German.  

 

I've not seen reference to PAS 'strength' being related to what angle the steering wheel is at, only to how fast it's being turned and vehicle speed.  The hydraulic mechanisms nearby automatically sort out the direction the fluid should be pumped to give assistance the right way. 

 

Also, in VCDS you can see 'angular velocity'/turn rate in a measuring block, but I'm reasonably sure I've never seen 'steering wheel angle'.

 

So I think the output of the G250 sensor is probably a simple PWM signal of 'turn rate'.