Completely Dead

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New Member
New Member
Posts: 2
Joined: Wed Apr 07, 2021 5:51 pm

Hello, I am an HVAC contractor in western NY.

I have a 15kw 0043902 serial number 3859423. It is completely dead. Last year I replaced the battery and voltage regulator for a different issue. On a whim today I checked the generator and found it had no green light, no red lights. I switched from Auto to Manual and it did not start. No clicks, no noises whatsoever except the ever-present hum of the battery charger. I checked both fuses. Both are good. The system fuse pulled of course reset the system and now the red LEDs are blinking erratically, except for the over crank, and the green LED sort of flutters in and out. Eventually the LEDs all go out and overcrank comes on but nothing has even attempted to start. Trying the switch for setting the exerciser results in nothing. No clicks, no noises, nothing.

Because the LEDs are going wonky and there's no attempt to even try to start I'm thinking the main control board has pooped. I haven't been able to diagnose further as I stopped there with no tools just to get a water softener model number.

Your thoughts?
Generator Guru
Generator Guru
Posts: 780
Joined: Mon Apr 20, 2020 5:59 pm

First off, before replacing control board, try a brand new known good battery. A lot of times the onboard battery charger can fail which kills the battery over time.

That unit uses battery charger 0A18010SRV. The easiest way to check the charger itself is to check voltage at the 2 terminals on the battery charger. The top 3 pin terminal on the charger should product about 13.2 VDC across the outer 2 pins of the charger unit. The other test involves the lower 2 wire connector. The wire leading from the transformer to the charger should test aprox 16VAC.
19955A20-5DEE-4E66-B291-FA551E614254.png (178.31 KiB) Viewed 84 times
Site Admin
Site Admin
Posts: 3824
Joined: Sat Aug 04, 2018 8:46 pm
Location: Clawson, MI

I'm with GRS. Sounds like a dead battery to me!

The charger he's talking about is here: ... a1801-more
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