I tried an intilization like you mentioned I'm sure I've done this in the past a few times. It worked okay for about a day, the next it went back to it's normal hot temp boot limbo. When I disconnected the battery, it was in the afternoon and not a particularly hot day the next day. I may try to force initialization again on a hot day to see if that does anything. I left the battery unhooked for about 5-10 minutes.

I did remove the radio to check connections. Neglected to find my multimeter, but connections like good. Nothing obvious for burns, melting or chaffing. Radio fans did work. I did see if voice command would work when the radio was in its limbo, it would not function. Not particularly suprising but wanted to cover all of my bases.


Bare dash


Radio/CD assembly


Monitor assembly

Helpfully this helps spark some insight into these modules and their issues. I have not called United Radio yet to get their insight into the issue. Hoping to gather more information so I can better describe what's going on.

Thanks again everyone for the help!

 

The main reason you should not use an AGM battery is that the flooded cell charging system has a higher “float voltage” and will over charge an AGM battery. You might feel of your battery case to see ir it is getting unusually warm.

 

I'll take the temperature of the battery cold and hot throughout the next hot day or so. From what I could find on google, this battery has a 13.6-13.8V float charge while most flooded lead acid batteries have 13.5V. I'm unsure if I'm understanding exactly what your saying on this one, so I may need to crash course this a bit.

Despite this being a possibility, why would this only happen in summer temps when the car has sat in the heat for some time? I'd think if the battery temp is rising and causing issues, wouldn't it cause more issues once the car is at operating temp under the same conditions?

In the morning commute to work when its cooler, the radio usually has no issues. By lunch time and the temp has risen, especially inside the car (obsidian color). The radio likely doesn't boot until well into my drive/lunch. Similar for end of the day in summer time. Once winter and fall has come around, the issue goes away. Rinse and repeat for the seasons.

I understand the battery is not exactly the battery type it came with, but even a battery likely doesn't have this much sway on one specific module under specific conditions. Navigation (minus audio/ voice commands), HVAC, amplifier monitor assembly all work normally when the radio is in this boot state. I don't have any other issues with anything else.

The only real thing I could think of is the module is failing or potentially a communication/wiring issue. The only reason I doubt the latter is because the radio works fine once it's on with no input lag or input errors. The radio doesn't have issues once it's finally running. Audio is clear, responds well and I've never had it stop working once it has finally turned on until the car is turned off and has sat for some time.

 

I agree with everything you said. I’ll try to be more judicious with my future comments.