Castlegarden ride on keeps cutting out when cold volts going up to 16.2

Question edited to add Maker.

Likely to be a drive belt issue.

7 Reasons Why a Riding Mower Won't Move Forward or ...

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Mower drive belts slipping is major reason some riding mowers won't move forward or in reverse. These belts connect the energy produced by the motor to the axle ...

add an additional 6 volt power wheel battery in series with the 12 or even use two 12 volts see you tube for examples

Hydrostatic or geared transaxle??

call factory service and ask. phone number on sticker on machine and in owners manual. I assume that you have some kind of ride on lawnmower. also, no one ever thinks of reading the owners manual troubleshooting guide. of course before you can read it,first you have to find the owner's manual. You can download a pdf owners manual from the manufacturers website.

some engines have a low oil level sensor yes. ck. oil level

put a volt meter on the battery and check the voltage around 12.5 volts then start the engine and watch the volt meter it should go up to around 14volts keep in mind a riding mower battery is only good for a couple years if stores charged during the cold months

sounds like you need to test the safety switches with a ohm meter start with the one on the seat then check the one on the clutch/brake pedal the look at the one in the reverse position

First off a fully charged 12 volt battery should read above 13.6 volts DC, and easiest way to test if the battery or starter are bad is to jump the positive post on the battery directly to the starter side large post of the starter solonoid, if the battery and starter are good the engine will turn over if all it does is arch then the battery or starter are bad use jumpers from a good battery to the starter solonoid of the tractor and see if the starter turns the engine over if so then battery is bad if not the starter is bad. Hope this Helps Don