4 hours ago, J.R. said:

What "brain" makes the decision to brake the opposing wheel in response to all the sensor inputs, wheel speed, vehicle speed, steering angle, throttle opening etc, is it the ABS module or the ECU or something else on the can bus network?

 

I believe the ABS system makes the decision but will need to communicate with other modules to get a fuller picture of what's happening. There are certainly some MK5 Golf's with very similar engines to yours with MK60 fitted: https://www.mk5golfgti.co.uk/forum/index.php?topic=83107.0

 

4 hours ago, J.R. said:

I realise the ABS module does the doing but I want to be sure that my vehicle will do the commanding or its a waste of time fitting one. I presume something somewhere will need coding.

 

Obviously you'll need to code the ABS module. Other than that, I think I changed an adaption channel in 44 Steering Assist to enable DSR (Driver Steering Recommendation) which will make small corrections to the steering due to road conditions/wheel slip.

 

4 hours ago, J.R. said:

Read on one of your postings about changing the switch from ASR to ESP or vice versa, what is the difference between the 2 and what do I have at present? I will look when I go out to the car.

 

It'll either say 'ASR off', 'ESP off' or a '*Skidding car picture* off' but apart from the icon, it makes no difference. They are electronically identical but as I had fitted ESP, I wanted the *skidding car picture* version for completeness!

 

2 hours ago, Golf-Fiend said:

So if I feel the ABS pump kicking in when I got wheelspin as I did in the snow/slush earlier this year, then what system do I have? The bottom on the dash says ASR. 

 

It's easy to check if it's a MK60 or MK70 assuming your OBD scanner can tell you the part number of the ABS pump. At a guess, a 2005 Elegance with a manual gearbox probably has a MK70 but I can't be sure...

 

For anyone that's interested and fancies a read, try SSP374 from VW: http://www.vaglinks.com/vaglinks_com/docs/ssp/VWUSA.COM_SSP_374_Traction_Control.pdf

 

Just to point out:

- a MK70 has 8 solenoids/valves so it's similar to the diagram on page 18

- a MK60 has 12 solenoids/valves so it's similar to the diagram on page 37

 

It's the extra 4 solenoids that add the ability to build up brake pressure without needing driver input.

 

On cars with a MK70, they can only perform ASR/TCR by using 'Engine intervention anti-lock brake system'. The following is taken from page 34 of the above SSP:

Quote

The engine intervention anti-lock brake system E-ABS is an extension of the ABS system's functional scope. It is intended to support the driver on starting off and to prevent the wheels from spinning. With E-ABS, the ABS control system has the option of intervening into the engine management system. It is not able to actively build up pressure.

 

If, on the basis of the wheel speeds and the engine management system information, which are transmitted via the CAN data bus, the ABS control system ascertains that the drive wheels are in danger of spinning, E-ABS instructs the engine management system to close the throttle valve further and thereby reduce the drive torque.

 

E-ABS is unable to intervene hydraulically in the drive wheel brake cylinders. The system does not have the option or equipment to independently build up brake pressure via a pressurisation system without the involvement of the driver.

 

I played with the coding of the DSR but could not feel that it did anything, if it needed a MK60 ABS module its not so surprising, the description was wooly and I thought that it meant if the wheels were about to slip, say understeer it would nudge the steering a bit like a stick-shaker on an aircraft to encourage you to wind on more lock or opposite lock at the point of oversteer.

 

In any case it did nothing.