Replaceing HU-650 with best OEM radio available Topic is solved

gcha8e · Post by **gcha8e** » 25 Oct 2019, 13:57

My HU-650 has always had horrendous AM radio reception - the time has come. (or else trouble shoot the electrical system I suppose). My preference is to replace the 650 with the 850, will this actually upgrade the AM reception?

If not, I am willing to go to a modern double DIN radio with navigation screen etc.... it might be nice to have the Apple Car Play, but I think I'd prefer to keep the interior looking all Volvo.

The issue is that even though the signal is coming through there is a terrible buzz. Sometimes, rarely, I start the car and the sound is just fine.

I also want to make sure I keep the Speed Compensated Volume feature (ASC?) and function of all the steering wheel controls

Any advice appreciated!

Post by **oragex** » 25 Oct 2019, 14:03

A few ideas viewtopic.php?t=47425

gcha8e · Post by **gcha8e** » 25 Oct 2019, 16:34

Very helpful stuff. I was able to locate the wires to the back seat signal booster. nothing appeared wrong with it when I checked it for corrosion. (yay, one more fascia that has been pulled and never to go in place perfectly again

). I pulled disconnected/reconnected the little coax wire from the signal booster in the back seat and the antenna amplifier box in the trunk.

The AM has only a minor buzz but still, it may have been - it seems - a good day for AM..... further reports to come.

I seem to recall in researching this a few years ago and had found the number of the technical bulletin referenced. I actually called Volvo here in Kansas City and the tech told me he had never heard of such a bulletin. Have been living with the issue ever since.

gcha8e · Post by **gcha8e** » 30 Oct 2019, 07:51

Update: unplugging and reconnecting the cable on both ends that runs between the sub amp in the trunk and the antenna signal booster in the back seat C column seems to have resolved the AM signal issue. Both connections seemed to be in shiny new condition, so I can't really explain why this would be the case.

One additional tip for anyone with the HU-650 that has the problem of the unit randomly skipping from source to source (AM to FM to CD and back and forth rapidly). Lack of use of the Source knob (in favor of the presets) seems to build up some kind of oxidation on the internal connections between the knob and the unit. turning it a few times around seems to fix that for me.