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Maestro Troubleshooting MA-PRO FAQ & Troubleshooting Guide

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MA-PRO FAQ & Troubleshooting Guide

Troubleshooting the MA-PRO Dimmer


What you can do if the LED's you are using do not dim, have a poor dimming range, or they flicker or buzz?
  • Confirm if the lighting load is a dimmable. If so, try another dimmable LED. If that performs in the same way then you may want to use the Lutron Compatible lamp tool. LED Tool to find a compatible LED load.
  • Try Adjusting the low end trim on the dimmer. Click HERE for Low End Trim adjustment directions.
  • Connect the Neutral to the Silver Screw on the dimmer if you have a neutral connection and have not done this already.
  • Confirm that the dimmer is in the correct phase for the lighting load being used. Phase change instructions can be found HERE .

What does Phase Selectable mean regarding the MA-PRO dimmer?

The MA-PRO Phase Selectable dimmer has three settings that allow you to select between forward-phase, reverse-phase, and phase auto-select. Note: The default with no neutral connection is phase auto-select which in most cases will run in reverse phase unless the LED cannot operate correctly in which it will then automatically switch to forward phase. The default with neutral connected is reverse-phase.  For low voltage applications the neutral connection is required on the dimmer and reverse phase is used for ELV Electronic Low Voltage and forward phase is used for MLV Magnetic Low Voltage applications.

Why are indicator lights (ILs) 1 and 7 flashing?

When ILs 1 and 7 are flashing this indicates that the dimmer is in Over Voltage Protection Mode. You would first want to verify that the dimmer is set correctly for the lighting load being used. For example; If an Electronic Low Voltage load is being used the Neutral on the dimmer should be connected and the Dimmer should be set to Reverse Phase. Please see
Phase Change Instructions .

Why are the bottom three ILs 1,2 and 3 flashing on my MA-PRO dimmer?

The bottom three ILs flashing indicates the dimmer has entered Shorted FET Detection mode. This is a  result of a wiring error, wiring while the circuit is live (which should never be done) or overloading the dimmer past its rated capacity which may have damaged the dimmer permanently.  Double check wiring to make sure it matches installation instructions for the particular application.

What does it mean if all the ILs on the MA-PRO dimmer are flashing?

This would indicate that the dimmer is in Over Current Protection Mode. Please check the following;
  • Check Phase Select Mode to make sure dimmer is in correct phase for current lighting load.
  • Check that the LED lights are dimmable. Try another light to see if this performs the same way. If so, you can use the LED Bulb Compatibility Tool to find compatible bulbs for use with this dimmer.
  • Check dimmer wiring in accordance with installation instructions.
  • Power Cycle the dimmer by pulling the FASS tab out which is located directly under the large tap button. The press it back in to cycle the power.
Do I have to use a companion dimmer in a 3-way (two locations) or 4-way (multiple locations) application? 

Yes, a Maestro companion dimmer (model MA-R or MSC-AD) must be used with the MA-PRO for 3-way and 4 way control applications. The MA-PRO dimmer will not wire to a mechanical three way switch. Proper diagrams shown below.



Why are there are no ILs illuminated on the dimmer and the lighting load is off?

Check the circuit breaker to see if it is still Off or tripped. Check to make sure the lighting load is installed or connected properly. The dimmer must have a lighting load to operate properly. FASS tab must be pressed in in order for the dimmer to operate. Lastly, check to make sure the dimmer is wired to match installation instructions.

Why are the middle IL's flashing on the MA-PRO dimmer?

This error code represents an Over temperature Condition on the dimmer. Check the lighting load wired to the dimmer as this may exceed the maximum rating. See max ratings
HERE . The ambient temperature of the dimmer may also cause this if the dimmer is installed in a location that has a temperature higher then its ambient rating 104 °F (40 °C). Cycle power to the unit by pulling out the FASS tab and then pushing it back in to reset.

Why are ILs 3 and 7 flashing on my MA-PRO dimmer?

This error code on the dimmer represents a Line/Load Miswire detected. Swap the wires on Black and Brass screw terminals.