So I posted a while ago as had the issues below with no resolution, but due to similar issue with my old L322 Range Rover I managed to investigate and repair it.
Issue was all Radio channels sometimes would drop and show no signal on MMI. This would cause a 'pop' sound through speaker which was the AMP resetting, then after 30 seconds it would work again, some times would not happen for days and other times 3x in 5 minutes. Also if on a Bluetooth call I would notice I lost connection with the person on the call with the 'pop' sound but still be on the call and have full phone signal on MMI screen.
I already had new aerial fitted as Sat Nav lost direction (fixed issue) and felt maybe the ariel antenna booster at fault but didn't explain the Bluetooth call issue or amp drop out soo....
As per my Range Rover I removed the DAB, NAV, MMI module in the compartment in the left side of the boot. (DO SO AT YOUR OWN RISK I HOLD NO RESPONSIBILTY FOR YOU BREAKING YOURS WITH THESE STEPS)
I then took the unit inside and took the 5 screws out the bottom and 3 screws out the side, lifted the internal boards out by gently lifting up from the connections side and lifting out, turned upside down and sure enough white corrosion from years or moisture in air in boot compartment.
I cleaned up by spraying circuit board cleaner onto a soft detail brush and brushing lightly. I then fitted back in reverse order to removal, cleaned up Optic and Aux ports with a Optic cleaning click pen and refitted. Now it works perfect.
Issue was all Radio channels sometimes would drop and show no signal on MMI. This would cause a 'pop' sound through speaker which was the AMP resetting, then after 30 seconds it would work again, some times would not happen for days and other times 3x in 5 minutes. Also if on a Bluetooth call I would notice I lost connection with the person on the call with the 'pop' sound but still be on the call and have full phone signal on MMI screen.
I already had new aerial fitted as Sat Nav lost direction (fixed issue) and felt maybe the ariel antenna booster at fault but didn't explain the Bluetooth call issue or amp drop out soo....
As per my Range Rover I removed the DAB, NAV, MMI module in the compartment in the left side of the boot. (DO SO AT YOUR OWN RISK I HOLD NO RESPONSIBILTY FOR YOU BREAKING YOURS WITH THESE STEPS)
I then took the unit inside and took the 5 screws out the bottom and 3 screws out the side, lifted the internal boards out by gently lifting up from the connections side and lifting out, turned upside down and sure enough white corrosion from years or moisture in air in boot compartment.
I cleaned up by spraying circuit board cleaner onto a soft detail brush and brushing lightly. I then fitted back in reverse order to removal, cleaned up Optic and Aux ports with a Optic cleaning click pen and refitted. Now it works perfect.
