Extract from Honest John web site
"Remember, on snow and ice ESP is normally best switched off because it can fight a driver's reactions to a skid in super slippery conditions. But you need to find an open area and test this out for yourself before switching it off.
On hard packed snow, frozen snow or ice, ABS might actually prevent the car from stopping because it automatically releases the brakes on wheels that are skidding. If all four wheels are skidding it will release the brakes on all of them. So on snow and ice, think ahead and start braking gently a lot earlier than you would in normal conditions. This is particularly important descending inclines or approaching junctions from side roads where you could skid straight out of the side road into traffic on the main road." - I had forgotten all about this bit !@!@~
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