4wd warning lights on on 2004 Porsche Cayenne S

using diagnostic tools to diagnose, no fault code present.
vehicle can only select to low range, two option>gear reduction on or off, but cant select to ON ROAD drive. after select to ON ROAD drive, instrument cluster comes out ''4wd system fault''

Asked by for the 2004 Porsche Cayenne S
1 answer 1 comment
You will need to get the codes read out from the all wheel drive system, which your scanner may not be capable of.
i have replaced transfer case encoder motor and the range selection switch at the center console, they are working find...but the problems still exist...