Axiom Home Page Forums General Discussion Technical Questions EP500 not fully powering on

Greeting, Axiomites. I have come out of forum retirement because I require some subwoofer troubleshooting assistance. My EP500 v2 stopped working some time in the last month. The power LED either comes on orange (both green and red) or occasionally just red. I've tried unplugging it for a while and replugging, but it never flips to green and the driver remains dormant regardless of input signal.

When the sub was healthy, when powering on the sub, the LED would be red, but then the unit would make an audible click as the light switched to green.

I've checked the fuse and it's good. Am I missing any other basic troubleshooting steps?

Guess we could attempt to diagnose the problem long distance. How comfortable are you with electronics. And do you have a meter?

It's pretty bloody obvious what's wrong. You don't even have to be technical to figure it out. The sub's traffic light is busted so it's staying red. Therefore the audible clicker is just staying put waiting for the light to turn green so it can click. All you gotta do is ask Axiom for a new sub traffic light.

I do have a basic multimeter with probes and I'm comfortable removing the amp from the cabinet to poke around. I should probably pull it out and go from there.

Mojo, nice to see you're still keeping things jovial.

Make sure to always keep one hand in your pocket lest you ignite your 'nads.

Ok. First do a visual inspection … anything look burnt ?… any electrolytic capacitor look bad (do the tops looking bloated)? Anything loose?
No .. start checking the power supply voltages. Linear supplies are usually fairly simple. Mains into primary transformer winding with 1 or more secondary windings out (each supplying an AC voltage). Each winding goes to a rectifier (one to four diodes depending … sometimes in a single package) and then usually to a storage cap. At this point it’s a DC voltage with a bit of 60hz ripple. After this there might be additional circuitry but for now we just want to know how many secondary windings and measure the DC voltages at those caps. Your meters black lead goes to ground (try the case or heat sink) and then the meter’s red to one side of each storage cap or the other (one is ground the other should give a reading). If you have trouble… take some pictures and either post them or pm me for my email. Have fun.

If it looks like this, it's ready for trade-in.

Nice Mojo … did you have a flood?

Also Is that from a V2?

An electrolyte flood. Not me; a friend. It's an 800v4.

Oh … the cap exploded onto the xformer … the supply might be fixable for the price of some caps …
In any case you have some nice parts …

Axiom fixed it. Good practice for all the Brystons that will be getting refurbished.

Peter,
Being a tech person, I'm sure you know this ... but it occurred to me I should have stated it anyway:

The voltages in this thing can be dangerous ... especially at those big caps.
Also you'll need to wait a min and check them after turning off power because they most likely will hold a charge for a while.
Anyway be careful not to short them with a tool or though yourself ... Ok, now you can have fun ...

Peter, you should know that Rich is a P.E. and hence professionally responsible for all advice he gives you. Take comfort knowing that if you vaporize your cojones, you can sue Rich for new ones.

Mojo may be speaking from experience ... although I can't say anyone needed to warn me about such things ... I would imagine it's best to keep pants on while probing around

Unless ufo involved

UFO and a few other non-electronic activities

500
You don't have to turn on the red light
Your days are over
Trade yourself for a v4 from Dwight.

Good lord Peter is still alive.
There were rumours he became a swami and moved to the alps in northern Tibet to ponder the extremities between Apple and Android OS.