Weird noise and diagnosis

[niclemaitre]

Got to drive Rooies for a reasonable distance this weekend for the first time in ages and noticed a weird, high pitched singing noise coming from the engine bay area, or at least apparently so. The noise rose and fell with the engine revs, making us think it was a belt or similar.

We monitored it, but it seemed not particularly serious so we carried on. On the return trip it was there again, the moment we turned on the music. After a bit of fiddling we found that it was electrical interference coming through the sound system.

When the tablet that stores and plays the music is plugged in and charging, there is enough "noise" in the charging circuit that it bleeds over into the audio cable/audio out of the tablet and makes the singing noise. The voltage regulator that regulates the alternator output is obviously putting out quite "noisy" voltage and that's transferring through to the rest of the vehicle.

In the past, the tablet was powered by a 2.1A 12V to USB converter in a 12V lighter socket, and I don't remember the noise then. Now I've changed the lighter socket to one of the 2 female USB sockets from 4x4direct and I don't think that the damping is as good. I'll change it back and see if it makes any difference. Otherwise I think I should look at getting a better regulator.

[The Legend]

Nic where is your regulator? Build in the alternator or outside?

[The Legend]

Nic if you your regulator is inside your alternator .See attach tread from Cassie .It works like a bom if you need more voltage

http://www.hilux4x4.co.za/hilux-alternator/index.php" onclick="window.open(this.href);return false;

[niclemaitre]

The regulator is a separate unit.

[niclemaitre]

Switched the power supply's around and ya, the noise is much less with the previous setup. Also noticed that the battery/alternator light is flicking on and off fast, so maybe I need to get the alternator serviced