Recalibrate the Sunroof (One-Touch)

On a Magnum ordered with the power sunroof, a common quirk after the battery has been disconnected is that the vent (tilt) still responds when you hold the button, but one-touch Open and Close stop entirely. The glass has lost its position calibration, so the module no longer knows its travel limits. A short relearn resets the closed reference. This applies only to Magnums fitted with the factory sunroof, not the fixed-roof cars. Keep hands and objects clear of the opening while it moves.

How you know it needs a relearn

On the wagon the tell is that held-button vent still works while a single tap for full Open or auto-Close does nothing, typically right after a battery change or a headliner job. Because the Magnum’s roof opening sits under a longer roofline that catches leaves and road debris, watch for the other pattern too: if the glass drags, stalls or reverses partway, that is a fouled or binding track, not a lost setting — clear it before trying the relearn.

1. Turn the ignition to the Run position.
2. Press and hold the VENT button until the glass reaches the full-vent position and the motor has stayed stopped for at least one second.
3. Briefly press and hold the CLOSE switch, then release; the glass should travel to the fully closed position.
4. Confirm normal operation — one-touch Open and Close should work again.

Why it happens

The sunroof module counts motor rotations out from its stored endpoints to know the glass position and when to stop or auto-reverse. A battery disconnect erases those references, so it keeps the memory-free held-button vent function but disables the automatic one-touch modes until the closed stop is relearned.

If it doesn’t work or common mistakes

• Give the motor a full second stopped at full vent before pressing Close, or the endpoint won’t be captured.
• Clear the guide track first — the wagon collects more debris around the roof opening, so grit here is a frequent cause of an incomplete relearn.
• If the panel won’t reach full close or reverses on its own, stop rather than force it; that indicates an obstruction or a stored motor fault.
• Fitting a new sunroof motor is separate: the workshop must also run the multi-cycle excessive-force (anti-pinch) calibration, a safety step this basic position relearn does not include.

Because the wagon’s roof opening traps more debris, keeping the tracks and corner drains clear goes a long way toward preventing repeat calibration losses.