Jayco Greyhawk – AC Capacitor & Fan Motor Service

Walk into any Jayco dealer service department and they’ll tell you a failed AC capacitor means you need a new fan motor—$600 to $800 installed, weeks on the waiting list. Then you hit the RV forums and half the posts say “just swap the capacitor, the motor’s probably fine.” One of those voices is steering you wrong, and it costs money to figure out which. Here’s the reality on the Greyhawk: the dealer isn’t lying about the motor being stressed, but they’re skipping the actual root cause. A bad run capacitor forces the fan to strain for weeks or months before it actually fails. Replace only the motor and you’ve installed a fresh one that’ll burn out the same way in half a year, because the capacitor—the real problem—is still dead. This walkthrough shows you how to diagnose both, fix the capacitor first, then decide whether the motor actually needs replacing. That order matters.

Why the Run Capacitor Is Your AC’s Actual Weak Point

A dead run capacitor on a Dometic rooftop unit stalls the whole operation—the fan motor can’t generate enough torque at startup without it, so you hear the compressor trying to turn over, nothing catches, and airflow dies. The capacitor bridges the gap that lets the motor overcome its own inertia; without it, the motor’s just spinning in place while drawing current.

Parts and Tools

• Replacement dual run capacitor rated 60/5 microfarad, 370V AC, matched to Dometic 3312195.000 specification — check current price
• Needle-nose pliers or small adjustable wrench for terminal nut removal
• Multimeter with capacitance measurement function (or analog ohm scale for quick check)
• Insulated screwdriver set for rooftop access panel fasteners
• Replacement fan motor (Dometic 3312195.000 or equivalent) if capacitor test confirms motor damage — check current price
• Dielectric grease for terminal connections to prevent corrosion

Step-by-Step Instructions

Step 1: Kill power to the rooftop AC unit

Locate your main 120V AC breaker panel inside the Greyhawk and flip the breaker controlling the rooftop air conditioner to OFF. Wait 30 seconds, then use a multimeter set to AC voltage to confirm zero volts at the AC unit’s power terminals. This prevents shock when you touch the capacitor terminals. Do not skip this step—a charged capacitor can deliver a painful shock even after power is cut.

Step 2: Access the capacitor on the rooftop unit

Climb onto the roof with your multimeter and tools. Locate the Dometic rooftop unit and remove the access panel covering the motor and capacitor assembly—usually four to six Phillips-head screws on the unit’s side or top. Photograph the wire terminals and their positions before disconnecting anything. The capacitor is the cylindrical component mounted near the motor, typically held by a metal bracket.

Step 3: Test the capacitor before removal

Set your multimeter to the capacitance setting (or ohm scale if capacitance mode unavailable). Touch the probes to the capacitor terminals without disconnecting wires. A healthy 60/5 microfarad capacitor should read between 55 and 65 microfarads. If the reading is zero, below 40, or the meter shows an open circuit, the capacitor is dead. If the reading is normal, the motor itself is likely the problem—proceed to step 5 before replacing anything.

Step 4: Disconnect and remove the failed capacitor

Using needle-nose pliers, carefully loosen the terminal nuts on the capacitor’s spade connectors and slide the wires off. Note which wire connects to which terminal—take a photo if needed. Remove the mounting bracket bolt or clip holding the capacitor in place. Lift the capacitor straight out. Do not force it; if it’s stuck, gently rock it side to side. Keep the old capacitor for reference when installing the new one.

Step 5: Install the replacement capacitor

Position the new 60/5 microfarad capacitor in the same mounting location and secure it with the bracket bolt. Reconnect the wires to the terminals in the exact same positions as the original—this is critical. Apply a small amount of dielectric grease to each terminal connection before tightening the nuts. Tighten firmly but do not over-torque; hand-tight plus a quarter turn is sufficient. Double-check that both wires are fully seated.

Step 6: Restore power and test fan operation

Close the access panel and climb down from the roof. Return to the breaker panel and flip the AC breaker back to ON. Set your thermostat to cool mode and listen for the compressor to start. The fan should spin smoothly and quietly within 2–3 seconds. If the fan runs and airflow is strong, the capacitor replacement solved the problem and the motor is still good. If the fan still doesn’t spin or sounds rough, the motor is damaged and needs replacement.

Step 7: Replace the motor if it fails the test

If the fan did not start or runs roughly after the capacitor replacement, the motor is burned out and must be swapped. Return to the rooftop, kill power again, and disconnect the motor’s wire terminals and mounting bolts. Install the replacement motor in the same orientation, reconnect the wires to the same terminals, and tighten all fasteners. Restore power and test again. A new motor with a fresh capacitor should run smoothly and cool the rig normally.

What works

• Direct bolt-in replacement—no circuit modifications required, the dual 60/5 microfarad rating manages both start and run phases on the same motor circuit without deration.
• Superior dielectric material won’t degrade over time the way the original Greyhawk capacitor does; a full-timer gets years instead of a single season of reliable operation.
• Motor engages immediately on first startup and restores cooling capacity in minutes flat—zero parasitic draw, zero added strain on the compressor pump.

What doesn’t

• Terminal orientation is not forgiving—reverse the polarity by mistake and you have seconds before the capacitor vents or fails short, potentially tripping your breaker or cooking the motor windings.
• Some Greyhawks from earlier model years have lead spacing that doesn’t match modern crimp terminals, forcing you to hand-solder or fabricate custom leads instead of using push-on connectors.

I once swapped a capacitor on a flip Greyhawk and the motor hummed but didn’t turn—spent twenty minutes checking polarity before realizing the terminal lugs were corroded enough to block contact. Had to burnish every connection point with sandpaper before it caught. 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