Originally Posted by BOTUS

this came up on a Ford Forum the other day... might apply to your car too

Many antenna devices contain a small integral amp, so there are TWO methods to provide power to the integral amp depending upon design

1) phantom feed that sends power 5 to 12V back up the very same coax the signal comes down - this is the method most after-market devices use
2) German car manufactures prefer the more costly and pointless separate 12V feed

thus if Merc use method 2) and your device is only designed to use 1) nothing happens if you plug in the Merc GPS wire
The Ford GPS antenna can't be used with budget aftermarket android add-ons

I have the same fun retrofitting the Merc DAB Tuner on a European car -
I could upgrade to the Mercedes antenna that NEVER really function for $800
or
Fit an aftermarket one for $15 that works correctly all the time.
But when you choose to use the phantom feed supply the Merc DAB tuner can switch to - it throws a fake diagnostic warning

Originally Posted by Basso1001

It's 2007 CL500 with NTG 3.0. Vendor said it was for NTG 3.0 but when i strated op the new system i can only choose NTG 4.0 and up....