Coachmen Mirada – AC Capacitor & Fan Motor Service

Most RV owners walk into an AC failure thinking the whole cooling system is shot—compressor’s dead, refrigerant’s gone, time to call a mobile tech. That assumption costs them money and time they don’t have. The truth is simpler: nine times out of ten when a Coachmen Mirada’s AC unit hums but pushes no cold air, or when the fan blade barely creeps around before stopping entirely, you’re looking at a worn-out run capacitor or a failing fan motor—not a catastrophic system collapse. In a full-time rig, a dead AC isn’t just uncomfortable; it’s a genuine safety issue. But here’s the encouraging part: these repairs sit squarely in the owner-friendly category. The components themselves cost almost nothing, the mechanics are straightforward, and plenty of RV owners have already traced this path and left a clear trail behind them.

The Run Capacitor That Solves the “Humming But No Cooling” Problem on Dometic Mirada Units

A Dometic AC that hums without moving air almost always points back to the run capacitor. This component jumpstarts the fan motor on activation and sustains its rotation under operating stress. Once it dies, the motor lacks the electrical push needed to turn the blades—and if you catch it at this stage before the motor itself overheats and burns, you’re looking at a simple $40 swap instead of dropping $300 or more on a replacement motor.

Parts and Tools

• Replacement dual run capacitor matched to the microfarad and voltage rating on the old one (typically 60/5 MFD for Dometic units) — check current price
• Replacement fan motor assembly if the existing motor shows burn marks, seized bearings, or fails to spin after capacitor replacement — check current price
• Needle-nose pliers or small wire strippers for disconnecting spade terminals from the capacitor leads
• Multimeter set to capacitance mode to test the old capacitor before removal and confirm failure
• Flashlight or headlamp for visibility inside the AC unit housing and around the mounting bracket
• Small Phillips and flathead screwdrivers for removing the AC access panel and capacitor mounting hardware

Step-by-Step Instructions

Step 1: Kill power to the AC unit at the breaker

Locate your RV’s main electrical panel and flip the breaker labeled for the roof AC unit to the OFF position. Wait 30 seconds, then test the thermostat—it should not respond. This step is non-negotiable; the capacitor holds a charge even when the unit is off, and touching live terminals can cause serious shock or burn. Do not skip this.

Step 2: Access the AC unit and photograph the capacitor terminals

Climb onto the roof and locate the Dometic AC shroud. Remove the access panel (usually held by four screws along the perimeter). Before touching anything, photograph the capacitor and its wire connections from multiple angles—note which spade terminal connects to which wire. The capacitor sits near the fan motor, typically mounted on a bracket with two or three fasteners. This photo prevents reconnection errors.

Step 3: Test the capacitor with a multimeter

Set your multimeter to capacitance mode. Touch the probes to the two terminals on the capacitor. A reading near the marked microfarad value (e.g., 60 MFD) indicates a healthy capacitor; a reading of zero or wildly off-spec confirms failure. If the reading is close to spec, the capacitor may not be your problem—move to testing the motor itself before replacement.

Step 4: Disconnect and remove the old capacitor

Using needle-nose pliers, gently pull each spade terminal off the capacitor leads. Do not yank or twist—spade terminals bend easily and won’t reconnect cleanly. Once both wires are free, unscrew the mounting bracket fasteners (usually one or two Phillips screws) and lift the capacitor out. Set it aside; do not discard it until the new one is confirmed working.

Step 5: Install the replacement capacitor in the same orientation

Position the new capacitor into the mounting bracket so it sits flush and level. Screw it down finger-tight, then snug with your screwdriver—do not over-torque. Reconnect the spade terminals to the leads in the exact order shown in your photograph. Push each terminal firmly onto its lead until it clicks or seats fully. Loose connections will cause the fan to stall or hum without turning.

Step 6: Restore power and test the fan motor

Close the AC access panel and climb down from the roof. Return to the breaker panel and flip the AC breaker back to ON. Set the thermostat to cool mode and listen for the fan to spin up smoothly within 2–3 seconds. The blades should rotate freely and steadily. If the fan still hums without turning, the motor itself is likely burned out and requires replacement.

Step 7: Verify cooling output and monitor for 15 minutes

Once the fan is spinning, set the thermostat to your normal cooling temperature and wait 15 minutes. Feel the air coming from the vents—it should be noticeably cooler than the cabin air. Check that the fan does not stall, stutter, or make grinding noises. If cooling is restored and the motor runs smoothly, the job is complete. If the fan still fails to turn or the motor sounds rough, the motor assembly needs replacement.

What works

• Engineered as a direct replacement for Dometic 3312195.000 units with zero fitment fuss—microfarad specs are exact, connections are standard, and your fan restarts and spins the moment you turn the thermostat back on
• Built with reinforced internal structures to withstand the electrical surge that happens when the motor first kicks in, which is precisely what wears down OEM capacitors in year three or four
• Installation is a quarter-hour job total—climb to the roof, unplug the old capacitor, plug in the new one, and you’re back inside with cold air flowing within 30 to 45 minutes

What doesn’t

• Stock availability on Dometic-branded capacitors through general online retailers tends to fluctuate—the capacitor you find today might ship in two weeks, which defeats the purpose when the sun is overhead and your interior is 95 degrees
• A capacitor replacement won’t resurrect a motor that’s already locked up or has internal winding damage; if you spin the blade by hand and it refuses to turn smoothly, the motor itself has failed and you’ll need to move to solution number two

I’ve had the motor test spin freely, install the capacitor, flip the breaker, and then have the fan die again 10 seconds in — which meant I missed a partial short in the windings and had to pull the whole unit anyway. But 9 times out of 10, this capacitor alone resurrects a dead AC system. Fits for Dometic 3312195.000 Air Conditioner RV AC Motor Capacitor 60/5 MFD, Heavy Duty Air Conditioner Capacitor Replacement, Compatible with Dometic 3312195000 RV Air Conditioner Models

This post contains affiliate links. As an Amazon Associate, I earn from qualifying purchases at no extra cost to you.