Trailer Brake 16VDC power turns off--why?

[Beta V]

I have a ham radio connected to the trailer brake outlet (exposed behind the driver-side outer wall carpet.). This outlet provides 15.1 VDC and can support up to 20 AMPs (per spec). I've used this port for years on my 2017 MX without issue. However, on my 2023 MX, the outlet turns off intermittently. After a few seconds, it turns back on as if the vehicle is sensing an overload. The radio was transmitting on high power, but it does not draw more than about 8 AMPs. Is there something else at play? Is that circuit also feeding other devices? I don't have anything else connected to this low-voltage circuit. My additional concern is that if this trailer brake system cannot support low-voltage moderate to low-current draws, what will happen when someone is towing a trailer and this circuit shuts down?

Ideas?

 

[scottf200]

I plan to mount the antenna on the frunk lip. I didn't want to drill any holes and a mag mount
won't work for obvious reasons.
So, 16 VDC. Not cool. I'll look for a converter. The cigarette lighter outlet says it supports 12VDC @ 12-14 Amps. That might be enough as the radio draws about 10 A on the UHF frequencies.

Did you add something thing to convert 16 VDC to 12 VDC?

Aside: I use the same plug in my 2017 X for a travel fridge which I've used for multiple weeks straight. It has worked great.

 

[Beta V]

Did you add something thing to convert 16 VDC to 12 VDC?

Aside: I use the same plug in my 2017 X for a travel fridge which I've used for multiple weeks straight. It has worked great.

I wired nine silicon diodes in series (3 sets of 3) to drop the voltage. It measured 15.1 and I got it down to about 14.1. Yaesu said that 14.1 was fine--15.1 was not. The root cause of the failure was the diode assembly overheated and opened the connection.

 

[Beta V]

I have a ham radio connected to the trailer brake outlet (exposed behind the driver-side outer wall carpet.). This outlet provides 15.1 VDC and can support up to 20 AMPs (per spec). I've used this port for years on my 2017 MX without issue. However, on my 2023 MX, the outlet turns off intermittently. After a few seconds, it turns back on as if the vehicle is sensing an overload. The radio was transmitting on high power, but it does not draw more than about 8 AMPs. Is there something else at play? Is that circuit also feeding other devices? I don't have anything else connected to this low-voltage circuit. My additional concern is that if this trailer brake system cannot support low-voltage moderate to low-current draws, what will happen when someone is towing a trailer and this circuit shuts down?

Ideas?

View attachment 962798

I found the issue. Overheating diodes (I only had three in series) opened the connection. I built a new 3x3 array that seems to work better.