Dometic CFX3-35 Fridge Troubleshooting Guide
The Dometic CFX3-35 is a dependable 12V/24V fridge/freezer, standard on Timberleaf trailers. Most common issues can be solved with a few quick checks—even if you have no electrical background.
Tools Needed
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Digital voltmeter/multimeter
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Phillips or flathead screwdriver (for plug/fuse access if needed)
Step 1: Basic Power Check
Is the fridge turning on?
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If the display is off or the fridge isn’t cooling, make sure your trailer’s battery is charged and switched on.
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Check that the fridge is firmly plugged into the Engel-style 12V outlet in your trailer. (Timberleaf uses the two-pin Engel connection, found beneath the removable “cigarette lighter” tip on the fridge’s cord end.)
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Try unplugging and re-plugging the fridge. Wait 30 seconds to see if the display comes on.
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Check for error codes or beeping.
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If you hear beeping or see an error code, write it down for reference.
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Step 2: Test the Power Source
Test the 12V outlet:
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With the fridge unplugged, use your multimeter to check voltage at the Engel outlet in the trailer.
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You should see 12.6–13.2 volts with a fully charged battery.
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If voltage is below 11.5V, the fridge may not run, or may shut off to protect the battery.
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Try another power source if available:
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If you have shore power and the fridge’s AC adapter, try plugging into a regular wall outlet.
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If it works on AC but not DC, your trailer’s DC circuit may be at fault.
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Step 3: Check Fuses
Fuse in the fridge cord:
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Unscrew the tip of the fridge’s power plug. The cigarette lighter tip can be removed, revealing the Engel plug underneath (the one used in Timberleaf trailers).
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Inside the tip, you’ll find a small fuse—replace with the same type if blown (usually 10A).
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Fuse in the trailer’s fuse panel:
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Open the fuse panel inside the cabin at the foot of the bed (see Outlet Troubleshooting Guide for details).
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Look for the fuse labeled “Fridge” or “12V outlet.”
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Replace any blown fuse with the same type and amperage.
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Step 4: Fridge Settings
Battery protection setting:
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The fridge’s “HI,” “MED,” or “LO” battery protection determines when it shuts off to protect your battery.
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“LO” is recommended for lithium batteries—if set too high, the fridge may cut out early.
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Temperature setting:
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Double-check that you haven’t accidentally set the temperature too high (above fridge range) or too low (below freezing if you only want refrigeration).
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Step 5: Inspect for Physical Problems
Cord and plug:
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Make sure the cable and plug ends are not damaged, pinched, or corroded.
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Double-check the connection at both the fridge and the trailer outlet.
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Ventilation:
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Be sure the fridge’s vents have airflow. Don’t block them with bedding or gear.
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Step 6: When to Call for Help
If your fridge still won’t run, keeps shutting off, or displays persistent error codes:
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Note any error codes, voltage readings, and what you’ve already tried.
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Take photos of your plug, outlet, and any error screens.
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If your trailer is under warranty, Timberleaf can help with parts or service. If not, we can offer troubleshooting help and sell replacement parts if needed.
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Contact Timberleaf support or Dometic customer service.
Need more help?
Send Timberleaf a quick summary (including photos and any codes) and we’ll help get your fridge—and your camping—back on track.