Possible causes of fault: Notes

NOTE: The 'Diagnosis/troubleshooting' shown below is adapted to suit the fault type displayed in the tester (please note fault type numbering 1, 2,... etc.!). The fault memory Info key [F8] on the Porsche System Tester II No. 9588 can be used to read out the fault type in the 'extended fault memory'.

1.) 'Short circuit to B+': A short circuit to B+ causes the modulation pressure solenoid valve (main) to be continually activated
2.) 'Open circuit/short circuit to ground': A short circuit to ground prevents activation of the modulation pressure solenoid valve (main)
2.) 'Open circuit/short circuit to ground': An open circuit prevents activation of the modulation pressure solenoid valve (main)
3.) 'Electrical fault in electric circuit': Modulation pressure solenoid valve (main) has no or limited function