S60 Stereo/DVD: HU 850 No sound - Swopping circuit board with HU 803 circuit

[Chrismmoore]

My radio has suffered from the no sound except 5 second full volume bursts whether radio switched on or not. I've dismantled the radio to look for dry joints but couldn't find any. But the main circuit board looks burnt/overheated in one area. I purchased a second hand HU 803 unit (£35) that works fine but doesn't secure into the vacant location nor does the aluminium effect trim attach back on.
As the cheapest second hand HU 850 is £150 + p&p and also the HU 803 doesn't drive the remote volume and channel controls (backlights work fine) nor the reversing sensors; I'm wondering can I swap the main circuit board from the HU 803 into the HU 850 and every thing will work??

[Simon Jones]

I think you'll find the HU803 you've bought is pre-facelift (2004/5) whereas your HU850 is post-facelift so they are different shapes and mounting types. As the units are quite different I'd be surprised if the PCB was interchangeable.

If you end up going for an aftermarket stereo, I've got a fascia plate and all the wiring needed to fit a double DIN unit for £40.

[oragex]

There were two 'shapes' around the radio depending on the years.

How is the amp under the front seat, signs of corrosion? usually it's the amp that gives up.

The 850 wasn't near as good as the 803. Even a 603 is not bad but not great either, but bullet proof and works without the amp

[Chrismmoore]

Thanks, aftermarket looks fine but I was curious about how the connection at the back matched up so went for the sh volvo unit, so tell me how do the connection blocks work out are they the same or do you have to convert.

[Chrismmoore]

Originally Posted by oragex

There were two 'shapes' around the radio depending on the years.

How is the amp under the front seat, signs of corrosion? usually it's the amp that gives up.

The 850 wasn't near as good as the 803. Even a 603 is not bad but not great either, but bullet proof and works without the amp

Yes 803 worked fine straight into existing connector blocks my 850 was post facelift with plastic chassis chase for radio and cd plus alum trim. The 803 is pre facelift but abuts right up into that corner of the console where the alum trim would be. All wired through the amp under the seat (no corrosion)and works ok just no reversing sensors or steering wheel controls now.

[Simon Jones]

Originally Posted by Chrismmoore

Thanks, aftermarket looks fine but I was curious about how the connection at the back matched up so went for the sh volvo unit, so tell me how do the connection blocks work out are they the same or do you have to convert.

The aftermarket stereo comes with a standard ISO connector into which you connect the ISO to Volvo lead which then connects to vehicle's wiring. There is a second lead that converts the aerial plug to conventional type. You will lose the use of the underseat amp (if fitted), steering wheel controls, RTI voice guidance and parking sensor beeps. You can often buy a CANBUS adapter to regain use of steering wheel controls if required.