Chassis Radio powering only off House Power

[jellyjamblue]

Hello everyone. When I picked up my RV today my radio in the front chassis would not turn on . I thought WOW - thats weird. As I was pondering if I blew a fuse - I saw the house power was off - turned it on and the chassis radio went on.
I thought - weird - I don't recall it working that way...I had taken the RV in to RV dealer for they had to change the Sirius tuner since the old one was not working. I just still can't remember if I had to always have the house power on to turn the radio on. I email the rv dealer inquiring and the guy says " Yeah - we noticed that too - I guess when you changed out your original soundtream radio and put in the Kenwood at Best Buy they did not set it up correctly since the radio should power both off engine power and house power".
Honestly I just don't not ever recall this issue....would them changing the Sirius tuner cause this to occur ? You would think I would of experienced this in the past... getting older sucks let me tell you.
Is this an easy fix ? Any input would be appreciated.I asked the RV dealer for an ESt. to get it to power both ways .....waiting for there response. Its funny because the dealer did not change the radios - since Jayco did not have the soundstreams in stock and gave me a credit to get a new one. The RV dealer constantly reminds me " We did not do it - you had Best Buy install it "...etc..etc...

Thanks

[SloPoke]

Not knowing which year/model you have will make this repsonse fairly generic - our experience is with our Seneca.

Jayco wired our dash head unit to be powered by dual sources with an isolation module made up of two diodes. The intent was to supply power from either the chassis or house battery circuit and use the diodes to prevent back-feeding the house side with the chassis, and vis a vis.

If Best Buy (BB) decided to bypass the Jayco isolation module - then that would explain the symptoms you are facing.

[jellyjamblue]

Thank you for the reply SLoPoke. My motorhome is a 2020 Greyhawk Prestige 30XP.