no power to 12v circuit

[theracqueteer]

I have a Seismic 4113. The 12v circuit for the lights and refrigerator in the large slideout has no power. The fuse in the control panel is good. I pulled the fuse and checked with a meter across the fuse contacts. It showed no voltage. This is the only circuit that doesn't have power. ls there another fuse somewhere else that may affect this circuit?

[DonaandDon]

Does your Seismic have the residential refrigerator? Most all refrigerators run on 110 volts. Although my circuit panel is not labeld correctly (from the factory). I would start with cycling all breakers. I lost power once and the refrigerator did not come back on. All power was there but no lights on the fridge, until I cycled breakers.

[RogerR]

Do you have 12 volts anywhere? If not, start at the battery and work to the panel. Look a bad connection or fuse.

If you are plugged in to AC and the panel is not putting out 12 volts from the converter than look there for a bad ground, tripped breaker that provides 110 volt ac to the converter to make the 12 volts.

I lost 12 volts at the converter and it was a loose wire from the ground in the panel to the frame.

[theracqueteer]

There are a total of 14 12v circuits. 5 show voltage of 12.5 or greater. One shows only 7.5v and the rest show 0v.

[ALJO]

Look at the wiring under the slide maybe pinched or cut.

[JimD]

Testing for voltage across fuse terminals is not valid. In a circuit you will measure full supply voltage across an open only if the circuit is complete the rest of the way.

Think of it as a light bulb, switch, fuse, and a battery. With the switch turned off you would measure the battery voltage across the switch and not across the bulb or fuse. If you close the switch and remove the bulb you would measure the battery voltage across the bulb socket. If you remove the fuse, the only way you would measure voltage across the fuse contacts would be if the switch was closed and the bulb was good.

A better test is to measure from ground to each side of the fuse holder. One side should measure the 12 volts. The other side will be zero. Ohm out the fuse before you put it back in. It should read near zero ohms which means it is good.

If you measure 12 volts on one side and the fuse is good but nothing powers up in that circuit, you may have a bad fuse connection or open in the line from the fuse panel to the load. You could also have an open in the ground side of the load which would give the same symptom.

[theracqueteer]

Originally Posted by JimD

Testing for voltage across fuse terminals is not valid. In a circuit you will measure full supply voltage across an open only if the circuit is complete the rest of the way.

Think of it as a light bulb, switch, fuse, and a battery. With the switch turned off you would measure the battery voltage across the switch and not across the bulb or fuse. If you close the switch and remove the bulb you would measure the battery voltage across the bulb socket. If you remove the fuse, the only way you would measure voltage across the fuse contacts would be if the switch was closed and the bulb was good.

A better test is to measure from ground to each side of the fuse holder. One side should measure the 12 volts. The other side will be zero. Ohm out the fuse before you put it back in. It should read near zero ohms which means it is good.

If you measure 12 volts on one side and the fuse is good but nothing powers up in that circuit, you may have a bad fuse connection or open in the line from the fuse panel to the load. You could also have an open in the ground side of the load which would give the same symptom.

Thanks for the reply. After your explanation of how to do it correctly. I went back out and checked today. All circuits show about 13v. All fuses tested OK. Tried all switches at the control panel. Interior light switches 2 & 3, Ext 1, water pump and water heater not functioning and no 12v to refrigerator.


It goes back to the dealer Wed. for other work above my expertise so I'll let them trouble shoot.