It worked for a few weeks after purchase then stopped - no light on the button. GAP IID tool reported fault (lost contact with PAM) and so after trying various 2nd hand units that didn't fix it I bought a new one and at least got a flashing light on the button and no fault showing in the GAP IID tool but still not working. Used a bat detector to test the sensors front and rear with the car running and in D and R and there is no ultrasonic output (only the earlier cars have an audible click). Need suggestions of what to do next? 2012 TDV8 Vogue (L322)

Delved a bit deeper with the GAP IID tool and even though no fault is showing during a scan if I go into the parking assist ECU and run a scan lo and behold it shows fault with rear left inner sensor! 2012 TDV8 Vogue (L322)

Got there in the end.

Nice one.

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport