Eco start on Honda eu3000 not working

All it does is tell the ECM to a c t i v a t e the stepper motor (on the top of the carb) to the base idle speed which is the lowest permissible speed (revolutions) that the multi pole DC generator head produces enough DC current (Amps) to excite the inverter section and make ac. If it's not a switch issue or broken wire, it's an ECM issue and no point in dealing with that as the parts are expensive with a Capital E.

I had a 10 plus year old Yamaha 2800I open cradle Inverter that the economy switch was developing a mind of it's own (ECM issues) so I sold it. Ran fine, produced flawless 60hz PSW 110 current but the econ switch would engage sometimes and sometimes not. Could have been dirty contacts, could have been a bad Molex plug but I figured why bother. Just off it and get a new (cheaper) one.

Rather than incur the expense of an ECM (300 bucks on Flea bay), I sold the unit (Honda's and Yamaha's hold their value well) and got a Champion and kept some money in my pocket.

2oldman wrote:
Was there a load on it at the time?

I dont know the answer to this question or some of the others since it is dad,s gen. He just mentioned it wasn't working so I wondered if there was some known or common causes. He is going to begin diagnosing it starting with a potential bad wire or switch. He's pretty good w that stuff so we,ll see.

Was there a load on it at the time?

If I remember it right, those generator showed about 17 years ago as I bought my 15 years ago and it was still new animal in RV community at the time.
The ECO switch works with some delay, so make sure you are not missing that. As pointed above, it is switch you should turn to on after some warm-up period. Are you pulling the choke for start?
If the switch still doesn't work, I would pull front panel off and check for broken off wire.

Proper procedure is always start the unit with the 'Economy' mode off, never on. You switch is probably fried. If it isn't the switch, it's the ECM and if it's that, forget about it. Too expensive to replace.