CPU Wiring Help Needed - HKS CAMP
 

I’m trying to hook up an HKS CAMP system in my 2000 Boxster S. This is a computer system that interfaces with the car’s computer and displays data on a TV monitor in the car. Any way, I need to hook up three wires from the HKS system to the car’s CPU/ECM. There’s RPM, speed, and fuel injector. I just need to tap into one fuel injector line. I’ve got that part figured out from the wiring diagrams for the car. What I can’t figure out is the speed and RPM. It is not clear at all from the Porsche or Bentley manuals where the tachometer gets it signal from. I assume it comes from the computer in the rear trunk. Also there are Speed A and Speed B wires/sensors just to confuse things. Any help as to which wires I would want to tap into from the ECM to grab the RPM and speed signals? I’d prefer to grab all three signals in the trunk at the main CPU.

Also, any idea on the injector size (cc/min) for the 2000 Boxster S?

Last questions – if I wanted to hook up gauges for oil pressure and oil temperature how easy is this to do? Do I need to install my own sending units at the engine or can I tap into the signals from the OEM units? It looks like oil pressure is measured from a switch that probably just triggers when pressure is too low. So that probably wouldn’t work for getting variable data. It looks like the OEM oil temperature signal would work though.

Thanks!

Kirk

I'm not sure as to wiring in the HKS computer, but I can tell you that for oil pressure you will need a Carerra oil pressure sender, which is easy to swap, and one more wire for actual pressure signal, not just the idiot light. I believe the factory temp sensor will give you a readout. As to injector size, not sure, nor am I sure where to grab those other signals from. I would think you could figure all this out from the bentley diagram? I've used mine with much success for wiring

Patrick

Thanks Patrick. I've been all over the Bentley and Porsche wiring diagrams and I can't find a wire labeled "RPM" or "TACH" or "TACHOMETER". I've found "Speed A" and "Speed B" though... So I'm a bit confused about where to grab that tach signal. I could always get it at the instrument panel itself, but I've got the HKS CAMP under the passenger seat and I already need to run wires to the trunk to the CPU. So I'm just trying to make the install easier by getting all of the signals (RPM, speed, fuel injector) from the CPU. I've got the fuel injector part figured out, it's just the speed and RPM that are confusing.

I'll look into getting the Carrera oil pressure sender. That sounds like exactly what I need for a variable oil pressure signal, thanks again!

Kirk

On Porsche's the tach signal (TN signal) is always purple with a black stripe. You can pick it up at the cluster or at the DME. On your 2000 I believe it is the white plug pin 15 on the cluster and on the DME it should be plug IV #17. You can pick the vehicle speed up at the cluster as well (white plug #16, wht/brn wire). It comes from the ABS computer via the abs sensors wire. It can also be picked up at the DME via the wht/brn wire on plug IV #22.
The speedometer A signal is for things like the speed dependent volume on the radio.

Todd

Thanks!!!
 

Todd, thanks a bunch man, that is EXACTLY the info I was looking for. I should now have the install finished by tomorrow night and be all ready for a PCA tour this weekend. I don't care so much, but my wife wants the car looking and working perfect. :-P

Good luck with the X51, like others, I will be watching your posts very closely as this is the direction I would like to go in the future...

Kirk