IS250 Won't Start

[ZX10R NIN]

My cousins car has the issue of not starting & I'm wondering if anyone on PH has had this issue or has access to a wiring diagram.

You press the button the steering lock comes off all the dials but the starter motor won't fire, on the live data it's showing the car in park on both the gearbox & engine ECU's, there's a signal coming of the switch but it's not reaching the starter motor.

If I put power to the starter motor the car will start & you can drive it normally but when you stop you can't restart it.

Help.

[Oldandslow]

Olde worlde approach - check the starter relay, might not be closing when it gets the start signal or might not be getting the signal.