2006 Range Rover 4.2 full size

I'm getting code on display reading - front left tyre not monitored. Rotated the wheels to the back and getting same fault on front left tyre so I ruled out the sensor. Wanted to know how to determine if the problem is the antenna or module.

Here are my GAP tool readout:

TPM-Tyre Pressure

C1A56-16 (6 Front left tire pressure sensor and transmitter assembly - General electrical failure - circuit voltage below threshold
( on 11-02-2017 19:54:41 at 59956 mi )
C1A56-91 (6 Front left tire pressure sensor and transmitter assembly - Component failure - parametric
C1A56-93 (6 Front left tire pressure sensor and transmitter assembly - Component failure - no operation
( on 12-02-2017 00:04:05 at 59990 mi )
C1A56-31 (2F) Front left tire pressure sensor and transmitter assembly - Frequency modulation/pulse width modulation failure - no signal
( on 12-02-2017 00:01:59 at 59988 mi )