I just bought a used Secondary Air Injection Pump and it has exact same pitch noise issue. Can someone explain why X300 Secondary Air Injection Pump has three input wires instead of two input wires like any other Secondary Air Injection Pumps? I am think of making a bracket and uses Secondary Air Injection Pump from later jaguars.

 

The weird symbol at pin 1 is a air check valve solenoid inside the pump assembly

Took an X300's apart once as was not running , somehow water had gotten in there rusting it frozen

Referencing the parts catalog they have gone through a couple of part # changes and a TSB on uprating the fuse size

http://www.jagrepair.com/images/TSB/...ion%20Pump.pdf

and

http://www.jagrepair.com/images/TSB/...AIR%20Flow.pdf

See page 46 and 92 - 95 below

http://www.jagrepair.com/images/Trai...20-%202000.pdf