bcm sierra silverado body control module Voltage out from K9 Body Control Module only 4V ?

[Stig M]

Hi, I'm working with my new LED-bar which have a possibility to stay on during daytime with only positioning light. For this I was trying to get a 12V signal out of the K9 Body Control Module (BCM).

But, my measure instruments only shows 4 volt when Daytime Running Lamps (DRL) is switched on. Can this be correct? Anyone who have tested this before?
See enclosed picture of wiring diagram with yellow-marked the wire I measure on.

I might find a 4 volt relay somewhere on internet ( ? ), but want first to try find a solution with 12V relay.

Anyone maybe have other suggestions to get a 12V signal out when DRL is on?