Relay making buzzing noise

[bartyb]

This is for a 91 240sx with the stock DOHC.

The tail lights fuse kept on blowing, so I checked all the wiring going to the rear lights, all bulbs, all fuses, removed all the audio wiring left by the previous owner. The car alarm remains but it seems to be properly connected.

http://bart.sitesled.com/s13-%2091%20blue%20relay%2001.jpg

Yet once the car starts, a buzzing noise is emmited from this blue relay, which is positioned behind the wiring harness on the driver's side (just above the fuebox)

http://bart.sitesled.com/s13-%2091%20blue%20relay%2002.jpg


http://bart.sitesled.com/s13%20AT%201990%20-%20fuse%20box.jpg
Ignore the red dot, the blue relay is behind the harness on the bottom part of it, near a brown relay.

I am not sure what is his purpose, I'm guessing something to do with the VSS as once disconnected I have no speed indication. I changed it with another one I had in spare (without knowing for sure it is in working order as it came form a parts car), but it still makes this buzzing noise. Now Before I go and buy a new one from Nissan, is there a way to check if this is the problem, or what can be causing this relay to buzz like so? Once the relay opened, it looks ok, but I'm no electronics expert .

Also, the front side markers (orange) an the front white lights below the orange ones (DTRL Are they called?) are no longer working. I rechecked all fuses, nothing is blown now. There is another fusebox below the airbox that I didn't check yet though.

Any help in resolving this mess would be greatly appreicated.

[Max_PSi]

Normally if a relay makes a buzzing noise, it indicates that its not making or breaking the contact fully. Usually due to oxidized or worn contacts. But since the second one you tried did the same thing, it may be too low a volatge for the relay?

Just taking a shot at this, but whatever voltage that relay should see may not be there fully. Maybe you have a little short along the wiring to the relay.

[koukimonster139]

I had this problem with fuel pump relay. inside of it something had mechanically come apart like the armature or one of the other tiny parts and was flying around inside it causing a buzzing sound. When you opened it did anything fall out of the casing? im pretty sure they're not that expensive to replace but you can test the relay using a DVOM. check for resistance (ohms) and output voltage. a FSM will be helpful to know what the specs should be for the exact relay.