VW Passat 2001 Glow Plug Issue

2001 VW Passat
Engine code : AVB
Transmission: Auto

Lads having a problem with power going to the glow plugs.
I have checked all the wiring and all is good. I think the problem lies at the PCM controlling the relay.
Readings at the relay pins are as follows. (Relay removed).
:switch side pin 17 . Battery voltage at all time
:switch side pin 23. wiring good to 80A fuse(s125) then to glow plugs
:control side pin 19. battery voltage KOEO . 0 volts with key off
:control side pin 16. 3.58 volts KOEO. 0 volts with key off

I'm thinking i should not have that 3.58 volts on pin 16 witch comes from the PCM. Is this pin 16 going to PCM pin 42 ground side switched?
I'm also getting that 3.58 volts at the PCM on pin T121/42 and wiring from relay pin 16 to PCM pin 42 is good.
If this 3.58 volts should be there is it a bios voltage and what am i missing?
Thanks.
Mark