Disabling ABS
10-20-2002, 07:06 PM
#16
Rennlist Member
As I promised I am back with part numbers and illustration numbers for the factory ABS switching.
The ABS switching for the Euro RS can be found in the 911 C2/C4 factory shop manual, vol. VII. It is on the wiring diagram: "911 Carrera 2 model 92 Sheet 4B ABS Turbo Look", page 97-121. Look in field J/38 where it says "Only RS". Basically the wire from C32 of the central electronics board to terminal 15 of the ABS relay is interupted in two places in the Euro RS harness. A bridge is provided for insertion of switches at two points, one for a dashboard switch (Bosch Nr. 0340006012) and one for a master cylinder mounted high pressure switch (Part Nr. 964.606.901.70) The master cylinder switch allows the ABS to be turned off with high brake pedal pressure in a slide.
In the American Cup cars Porsche used a standard American wiring harness instead of the European RS harness used in the European Cup cars. So, to allow the ABS switching, a special harness (Part Nr. 964.612.003.75) was used for these cars that supplied the ABS connections of the Euro RS harness described above. This special harness also hooked up to the kill switch mounted in the trunk of the car, switching the connections between E42 and E32 of the central electronic board and turning off the DME relay. Without this harness the kill switch supplied in the US Cup car will not work because the alternator will keep the engine running even with the battery disconnected. These connections are also shown in the factory shop manual on the sheet: "92 911 C2 Carrera RS Different Circuits", page 97-147.
The ABS switching for the Euro RS can be found in the 911 C2/C4 factory shop manual, vol. VII. It is on the wiring diagram: "911 Carrera 2 model 92 Sheet 4B ABS Turbo Look", page 97-121. Look in field J/38 where it says "Only RS". Basically the wire from C32 of the central electronics board to terminal 15 of the ABS relay is interupted in two places in the Euro RS harness. A bridge is provided for insertion of switches at two points, one for a dashboard switch (Bosch Nr. 0340006012) and one for a master cylinder mounted high pressure switch (Part Nr. 964.606.901.70) The master cylinder switch allows the ABS to be turned off with high brake pedal pressure in a slide.
In the American Cup cars Porsche used a standard American wiring harness instead of the European RS harness used in the European Cup cars. So, to allow the ABS switching, a special harness (Part Nr. 964.612.003.75) was used for these cars that supplied the ABS connections of the Euro RS harness described above. This special harness also hooked up to the kill switch mounted in the trunk of the car, switching the connections between E42 and E32 of the central electronic board and turning off the DME relay. Without this harness the kill switch supplied in the US Cup car will not work because the alternator will keep the engine running even with the battery disconnected. These connections are also shown in the factory shop manual on the sheet: "92 911 C2 Carrera RS Different Circuits", page 97-147.
