Chassis battery

Could be. All terminals and cables in good condition?

If it just clicks but doesn't turn over the starter, probably a battery that has bit the dust. Has the RV been sitting unused for awhile?

Check battery connections
Check connection on battery side of the start relay.

Todays modern vehicles will drain the engine battery in about a week, if left unused.

Probably low on charge. Do you have a small portable charger to put on overnight?

Chassis start battery will get low on charge from just sitting same as any vehicle. Sitting low on charge battery will start sulfating and permanently lose capacity. Have it checked if charging does not help.

If the RV is plugged in consider a Trik-L-Start combiner to maintain the charge level on the chassis start battery.
http://www.lslproducts.net/TLSPage.html

ItsyRV wrote:
If it just clicks but doesn't turn over the starter, probably a battery that has bit the dust. Has the RV been sitting unused for awhile?

Yes ItsyRV due to the country being shut down it has been setting for quite some time . I have started it every couple of months but have had to use the house batteries to get it started each time.

time2roll wrote:

Chassis start battery will get low on charge from just sitting same as any vehicle. Sitting low on charge battery will start sulfating and permanently lose capacity. Have it checked if charging does not help.

Time2roll I have a feeling that is what has happened, tried to charge it and wouldn't take a full charge.

If that charger has a "recondition" or similar setting... don't hesitate to use it.

It can read 14.5 volts and still not have enough AMPERAGE to turn it over. The only real way to find out is a load test.
I just went through this with my diesel truck.....for the umteenth time (well, maybe 5th time in 20 years).
Time to run down to Costco and get the highest amperage battery that'll fit.

What does your chassis battery voltage indicate with engine off but with headlight switch turned ON? If below 10V your chassis battery is dead or badly discharged.