My 2000 has developed a whine which changes pitch with revs. The sound emits from the speakers but does not change volume with the radio. It’s not there all the time but now I’ve heard it I can’t unhear it! With the radio powered off the sound is gone.
Any ideas?
Cheers
Standard fit radio or aftermarket? Probably an earthing problem though in either case.
if your referencing a noise in the radio like the noise you got from an old car it could be the alternator starting to fail ?
I was fearing that…. Darn!
Better stick my spare in the boot!
Gilbertd wrote:
Standard fit radio or aftermarket? Probably an earthing problem though in either case.
After market now, where to start for an earth though…. There’s loads of earthing points!
Make sure the casing of the radio is connected to a good earth and not relying on the one in the power plug (assuming it is using standard DIN connections). It shouldn't matter which one you use as long as it is a clean earth. Failing alternator is a possibility. I recently bought one of these https://www.veconline.co.uk/new-replacement-12-volt-lucas-type-alternator-regulator-a127im-vrf153a-138789?search=282504162073 for the original Marelli alternator, set point at 14.7 volts too.
Thanks Richard
Also is the aftermarket stereo wired via the door amplifiers or direct to the speakers ? Incorrect wiring to the amps can also cause whine.
The amp is bypassed entirely.
The noise persists and have noticed it happens when the radio is powered off too. It’s not when engine is first started but after about 5-10 mins. Only while driving and definitely linked to engine speed (I can play a tune!)
There must be an amp that is still powered in there somewhere. You say the amp is bypassed, is this the DSP amp in the boot or the 4 individual door amps? There is a turn on signal from the head unit that causes the amps to be switched on (there have a permanent supply but stay off until a signal is seen on the turn on line). On an aftermarket install, but still using the amps, that would be connected to the electric aerial line. If you aren't using the amps, then there is no need to power them. They can't be fully bypassed or they wouldn't be connected to the speakers. It all depends on what you have and how it has been wired.
The amp is on the shelf in my garage, I completely removed it and hard wired the speakers to the stereo. My doors don’t have amps, it was just the one in the boot.
I did fit (I think on your recommendation) some crossovers so the sound wasn’t so muddy. Maybe they are failing?
Crossovers should be passive so no power there. DSP amp completely removed so how come the speakers are producing a whine? Is it possible that the output stage of the head unit is permanently on even when it appears to be switched off? You could try completely disconnecting the power to the head unit, both permanent and ignition switched and see what affect that has.
That sounds logical. I’ll remove the HU completely for a couple of days and see what happens