How do you fix the warmer when the lights on but it not hot?

Jason, I posted a trouble shooting link that explains how to test.
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HOT GRIPS heated grips hand warmers grip warmers

No warmer plate llight:
Usually means bad switch. Bunn Part no. is 20316.0001. Replacement available at link below.
Bunn Home On Off Warmer Control Switch Lighted

Note differences in switch wiring in photo below between old and new style switches.


Coffee not hot:
Make sure "Vacation Switch" is in OFF position.

Usually food warmers consist in trays of food sitting in a bath of boiling hot water. The hot water heats up the tray, keeping the food warm.
Most domestic food warmers are electrically powered.

there are many kinds of dish warmers available to buy or hire:
most company's use tea light heaters or water heaters.
Tea light heaters work by having a number of tea lights under the food to keep it hot. there are also electric warmers available but they require a power source.

So you have real toasty buns, eh? I would unplug the seat warmer for now.. Repair it before it starts a fire in your seat cushion, one of the warming elements has a problem. It will just have to be examined. Check with ford, maybe they have a solution that doesn't involve removing seat and tearing it apart. Sit lightly, wow, talk about being in the hot seat!

U have a AC refrigerant leak, that is why it worked for a week after the system was topped off, now it has leaked out again.

the catch is broken on the machine, so I havent been able to fix it

COFFEE PREPARATION PROCEDURES
1) Place filter into brew basket.
2) Put the proper amount of coffee into the filter.
3) Slide the brew basket into holder.
4) Place empty decanter on warmer located directly under the brew basket and turn corresponding warmer switch ON.
5) Pour decanter of fresh water through pour-in opening at top of brewer.
6) Hot water will be delivered through the sprayhead. This distributes the hot water evenly over the coffee bed within the brew basket. The coffee will drain from brew basket into the container below.
7) Red light indicates warmer is ON.
8) Before brewing next pot, remove brew basket from brew rails and dump filter into waste basket.

Please rate this a fixya

CHECK THE BLACK WIRE COMING OFF THE BOTTOM TERMINAL OF THERMOSTAT FOR VOLTAGE, IT SUPPLIES POWER FOR THE WARMER SWITCHES. THE 'READY TO BREW' LIGHT IS PROBABLY A BAD BULB.

Sounds like something is miswired from the factory. Note that the tank heater switch on most home brewer models also acts as the "master" power switch. If the tank heater switch is not on, the warmer switch will not work, either - this is normal. Under normal conditions, the tank heater (or vacation switch) should always remain on, except if you are leaving on vacation.