Originally Posted by Hdsechols
Have a 2008 GulfStream front end Cummins 300hp diesel. Issue is that intermittently when I turn key the, dash lights up, then I wait for start engine lite to go out and I attempt to start engine, but battery appears dead. Obviously battery is not dead as dash lights up. After a couple of starting attempts, the engine cranks. I checked batteries an have 12.75 volts. Also just made it home from a trip with battery lite on and 10.9 to 11.9 volts showing on dash volt meter. MH would not start until I used emergency start feature. Any suggestions as to culprit. Thanks
Ok ; I'm seeing a bunch of stuff that has to be looked into .
Your dash lights DON'T require too much in the way of power; and your starter does .
Bad battery connections , can light up the dash but not supply enough power to start.
Same for a bad battery.
Low battery light and 10.9>11.9 volts on gauge is very troubling . With the engine running the alternator should put out 13 > 14.2 volts .
So if the battery connections are good and the battery load tests ok then alternator output needs to be tested too.
Once the connections , battery and alternator have tested good , then you can start looking for issues with the starter relay , starter solenoid , neutral safety switch etc.