Audio system losing DAB radio

Faults and Technical chat for the Kia Niro
jerrytaff
Posts: 120
Joined: Wed Oct 03, 2018 8:28 pm

Post by jerrytaff »

USB adaptors cause problems with other cars too. I have a DS5 and I had to buy several different adaptors before I could reliably use the DAB while running a dashcam. The adaptors contain a 12V to 5V DC to DC to DC convertor which works by rapidly chopping the signal so it is off 7/12 of the time and on the remaining 5/12. It then filters the resultant pulsed waveform to get an average of about 5V. The switching transients put high frequency noise all over the 12V supply to the radio and to its earth return. If the signal in the radio receiver starts off fairly marginal, it does not take much in the way of interference to reduce the Signal to Noise to less than the threshold that allows it to reliably decode the digital signal. Of course it is not necessarily the USB adaptor generating the RFI, almost any of the electrical gizmos in the car could potentially do it; including the radio itself. All it needs is one capacitor or inductor that isn't soldered properly, or even a failing EMC gasket which completes the shielding of one box from another. So, I know of several cases with the DS5 where the entire radio/head unit / display was replaced before reception issues were solved. From my perspective, I find it quite an engineering feat to build a car this complex with so many sensors and electric circuits and have any reliability to speak of at all! Still, I guess its better for the DAB radio to drop out occasionally, than the ECU, or any of the safety critical circuits....

In the case of my DS5. on some days and and in some areas the DAB radio would work fine, and on others the radio would cut out every few seconds, requiring me to unplug the dashcam and /or smartphone before the radio would come back on again and stay on. Citroen gave me several firmware upgrades, and also checked the ariel several times before I realised what the problem was.

There is a newer form of DAB, DAB+ which uses more modern codecs than the MP2 used in DAB, and which, supposedly, is much more robust to interference. Apparently there are some stations using DAB+ in the UK, but I have no idea if the radio in the Niro is compatible.
2018 PHEV 3 in Gravity Blue :D
Previous DS (formerly Citroen) DS5 Prestige BlueHDi S/S Auto 2.0, Jaguar X type 2.0 S Diesel

deguy
Posts: 93
Joined: Tue Jan 31, 2017 8:54 pm
Location: Expat in Munich

Post by deguy »

jerrytaff wrote: Wed Oct 03, 2018 11:24 pm Apparently there are some stations using DAB+ in the UK, but I have no idea if the radio in the Niro is compatible.
I can receive all the DAB+ stations local to me, so the answer would appear to be yes.
Niro Spirit 2017 HEV in Ocean Blue (German spec similar to First Edition without ADAP)
Previously: Mercedes B-Class 200CDI Autotronic
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