The factory installed external CD changer needs to be removed/disconnected from the car completely if you want to use all functions of the Gateway (music playback). This is because the Gateway emulates these functions, and the car can only work with one CD changer in the same time. If you don’t remove them, any various problems may happen like:
- Volume changing automatically / randomly within 10-15 seconds or more
- CD changer (Gateway) as a source can or cannot be selected but it reverts you back automatically to radio mode shortly (within 2-3 seconds)
- Function buttons are not or only partly working (e.g. FFW)
- You cannot enter to the Text selector menu (BMW, section Q)
What to do if:
- Gateway is not recognized: This could also happen if the black grounding cable is not connected (in case of VW or Audi) or the installation is incorrect. It can also happen that the car side harness of the Gateway is damaged, to be exact the car configuration resistor on it is faulty (in that case it goes back to the default car configuration, which is BMW).
- Alternator noise: This is an extremely rare problem. If it happens, it means there is an issue with the cable or the hardware. Replacing the whole package (Gateway hardware and its car side cables) is necessary. If the problem still remains, then there is a problem with the grounding of the car.
- Gateway still not recognized by Mazda: Please check if the head unit has the L716 pin/transistor or not. If the Mazda head unit doesn’t have the L716, then the hardware of it is not supporting external CD changers, this means the Gateway can’t be recognized. Although we also met in really rare cases, that the L716 pin was on the board of the head unit, although in the software of the head unit the external CD changer was missing, so the same problem was in that case.
Gateway still not recognized by Toyota: In that case it is possible that your car head unit supports external MiniDisc changers instead of CD changers, so you may need to try the MiniDisc changer configuration. You can find the configs here with installation instructions, please try both the MDC and the CDC configs if nothing helps: