is the radio in the volvo fh 12 or 24v,just asking cos i got another stereo with bluetooth an ipod aux input,so dont want to blow it up by just plugging it in.
if in doubt, get a multimeter on it 
it should say what voltage it is on the back of the original radio, but most are now 12 volts run through a dropper but if still in doubt as sone else said multi meter 
had the radio out an the label so badly damaged you cant read it,i’ll take the multimeter with me tomorrow,got home tonight so its a job for wen i park up tomorrow night
All the Volvo’s I ever had were 12v radios. first thing I did with each one was to change it.
swapped the bog standard one for a 12v one and it hasnt blown up yet 
thats saved me asking the question, should be getting a brand spanker myself next week.
Yep they’re 12v with ISO connectors, piece of ■■■■ to replace. Youmcan get an adpator cable if the one you’re replacing it with isn’t an ISO connectors. If itmdoesn’t hold memory with the ignition off you swap the constant live and ignition live. The wiring on my replacement radio showed how this was done.
No if somebody can tell me how to connent my steering wheels controls to my radio?
i changed the radio in the fh and it worked fine till i smelled a hot smell,went to turn the volume control an could hardly touch it,it was so hot,had to take the face off an let the radio cool down,anybody have any ideas wots causing it
bobbert_bear:
i changed the radio in the fh and it worked fine till i smelled a hot smell,went to turn the volume control an could hardly touch it,it was so hot,had to take the face off an let the radio cool down,anybody have any ideas wots causing it
I’m not radio engineer but I’d say it’s {ZB’D} 
bobbert_bear:
i changed the radio in the fh and it worked fine till i smelled a hot smell,went to turn the volume control an could hardly touch it,it was so hot,had to take the face off an let the radio cool down,anybody have any ideas wots causing it
Is it a fancy head unit you have used? Could be drawing the max, or even more, power than the dropper is rated for. Some Alpine head units draw more than most for instance.
its a tevion with cd memory card slot usb bluetooth and aux for ipod,tried it in the car an work perfect no heating up at all
bobbert_bear:
its a tevion with cd memory card slot usb bluetooth and aux for ipod,tried it in the car an work perfect no heating up at all
I just had a look at the user manual for the Tevion and the wiring section shows the power leads protected by a 15 amp fuse. That suggests to me it does draw quite a high current for a head unit and is probably more than the 12v dropper in the Volvo is rated at, which is probably 5 or maybe 10 amps, so the dropper could be working at near capacity and all that results in the overheating of the unit.
In the car it’s not being fed through a dropper, just a straight 12v feed so it can draw the current it needs with no overheating problems. I think the solution would be a better dropper to provide the feed for the head unit.
would it be better putting the radio on its own dropper then,an if so,what amps one should i use?
bobbert_bear:
would it be better putting the radio on its own dropper then,an if so,what amps one should i use?
Probably, and as the power leads are protected by a 15 amp fuse a 15 - 20 amp one should do it.
if i wanted to change the one in the fh for a bigger amp one,where is it located
bobbert_bear:
if i wanted to change the one in the fh for a bigger amp one,where is it located
No idea.
just bought another dropper,so i’ll get the new stereo fitted back in when it arrives