2005 Discovery generator problem

[brianseay1]

A buddy of mine is looking at buying a 2005 Fleetwood Discovery J model. It has 27,500 miles on it and has been garage kept. Coach looks great. The problem is we can't get the generator to start. It had bad batteries, and new ones have been installed. But it will not turn over. The dash switch does not light up when you push it to start. The switch on the generator will light up and throw a code. at first it was 3 rapid flashes followed by a hesitation and then 3 more rapid flashes. Once i get it in the mode to check it will flash code 4-6. The batteries are fully charged and wired correctly. can't figure out why it will not start and why I don't have an indicator light on dash switch but I do have it on generator switch. The owner said he has never had an issue with it starting until the batteries went bad. My buddy knows the owner real well, so we know he is on the level with us. We had found some of the electrical things were not working, but that was due to a tripped GFCI circuit. Any help is greatly appreciated.

[larry_cad]

Troubleshooting list of codes and repair suggestions for Onan

[brianseay1]

donkeydew wrote:
are you holding the switch down long enough for the glow plug to heat? mine usually take at least a minute and a half before the engine starts turning over

I'm doing it the same way I do in my coach. In mine, as soon as I hit the button I get the green indicator light flashing and you can hear it going thru the steps to start. On this one, you can hit the button and nothing is happening. You go out and hit the switch on the generator itself, the indicator light comes on and starts rapid flashing the code.

[brianseay1]

bgum wrote:
Did I miss brand and model of generator?

sorry about that, its a Onan superquite7500 diesel.

[donkeydew]

are you holding the switch down long enough for the glow plug to heat? mine usually take at least a minute and a half before the engine starts turning over

[bgum]

Did I miss brand and model of generator?