How do I up the temp on my systempool jacuzzi

Sounds like a child safety feature.

Does the jacuzzi pump motor get hot? Check any filters, make sure all valves are set correctly.

If your hot tub is running but NOT heating then you need to look at a couple of things.
First, on the topside, is the heat indicator light on?
If it is on and the tub is not heating then the temp sensor or the high limit sensor is not working and need to be replaced.
US Parts Center

this is the nature of the error code displayed.
(---) =Unknown water temperature. (Displays when first powered up after refill).



RodUS Parts Center888-521-6183

This is a bad main board issue

use a color back wax found in auto parts store to restore