3 way fridge not working on 12 volt have checked with volt meter 12 volt not present at dc terminal fuse seems to be ok.

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Question moved from Cars to RVs.

https://www.google.com/search?q=2012+mesa+ridge+fuses+location

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You may need someone to help on this one. First thing, check all the 12VDC fuses for your Jayco. It has mini blade style fuses. Using a multimeter or a probe, check for voltage on both sides of the fuse. Next you need to access the back of the switch to confirm you have voltage going in and out when depressing the switch. No power, get a new switch. Yes to power, proceed to next part.

If you know exactly which fuse if for that slide and you do have power, an ohmeter can be used while someone else is pushing the switch the retract. Most of the fuses are 20A, so you should be getting much less. You can also do a comparison between each of the slides. Keep in mind the bigger slides are much heavier so the amperage draw will be higher than smaller and lighter, but still under 20A. If no answer meter or amp clamp type of meter, a multimeter can be used on the DC reading and watching the voltage drop as the switch is pressed. If you do not have amperage or voltage drops, might be a loose or cut wire. If you do have drops and nothing happens, most likely the motor has seized and will need replacement.

connect a multi meter across the battery terminals and set on volts dc there should be 14.5 volts across the posts when the charger is on check for the dc notice on the dial as if the rectifiers in the charger have failed , you will get an ac voltage and that will not charge a battery

First, I'm not a Coachmen RV Tech. (but most DC to AC inverters are not brand specific.)
* Check inverter fuse (on actual inverter frame). Replace.
* Check DC voltage at inverter. Should be 12 (or 24 VDC) depending on your system battery supply and inverter.
* Check the DC cable connections; crusty, dirty? Cut all power. Remove and clean terminals. Re-connect and check.
* DC okay? Check 110 VAC power at output of inverter. No power? Replace inverter. (possible power spike damaged it or it over heated)
* 110 VAC okay? Check the power panel breakers. If stuck in middle then turn all the way off to reset and turn all the way back on to activate. Check AC power at outlet(s)
* Still no power (at outlet)? Check all outlets. If some still works then there is a problem with the power (wires) distribution. You will need an electrician to trace the wires back to the break in circuit.
* Be safe. check your warranty and call for service.
* Note; your inverter may be on a separate warranty.
Aloha, ukeboy57

The furnace and fridge both have control boards that may have problems. First check both circuit boards for built in fuses. Hopefully this is the only thing gone Replace the fuse and you should be good to go.

Locate converter and check for blown fuse(s) on converter first.

Not sure what kind of trailer you have, but the fuses should be behind a metal cover - for mine, its located under the refrigerator. When you open it, you will see all of the fuses. Hopefully, they are labeled, but don't bet on it. Use a meter to check the fuses - put the meter tip on each side of the fuse, with the meter on volts. If you read 12 - 14 volts, the fuse is blown. A good fuse will not show any voltage.

If you can't find the fuse box, when you have the camper plugged into AC, turn on all the lights - the fan that cools the inverter should come on - follow that sound and you will find the fuses. Good Luck

use a meter to check the sockets for voltage either 110acv or, 12v dcv
if dcv it's is your batteries or inverter not supplying power check with a meter set on dc volts; if ac check your circuit breakers with a meter set for ac volts if these are fine then replace switches