Fuel pump relay -to- vems

[lost]

Plan is to use "ground to turn on circut", to turn on fuel pump with Vems, problem is that on pin 85 wire that goes to vems i see +12v on DVM , but if i connect it to ground relay clicks and turns on fuel pump.
What worries me is this "weak" +12 that goes to Vems is going to kill something? Plan is to connect it to spare IGBT to ground that fuel pump relay...

URL=http://img35.imageshack.us/i/relaycircuits.jpg/][/URL]

[mattias]

You see +12V there because that's what's on the other side of the solenoid (pin 86) when there is no current running through it. No current = no voltage drop = +12V on both sides. If you force it to ground through the current measurement of your DVM you'll see 200-300 mA current (typically). It's supposed to be this way.

[lost]

But i can connect that pin 85 (relay gnd) to vems to turn on fuel pump? It wont kill p259 or something i hope.

[Sprocket]

But i can connect that pin 85 (relay gnd) to vems to turn on fuel pump? It wont kill p259 or something i hope.

You need to use a suppressed relay, either a resistor or diode that bridges the +ve and -ve of the coil. Otherwise you risk damaging the P259 chip.

Other than this the relay will not damage the Vems unit. Avoid any sort of dead short as this will surely kill the chip, so be double sure your wiring is right, which goes without saying with any wiring.

Edit** just realised you intend to use IGTB, in which case the relay does not need to be suppressed. Your last comment one the p259 chip confused things a little

[lost]

Ok, thanks , just needed confirmation that igbt is safe  ;)
Don't want to use p259 for anything to avoid future problems.