Display shows Err7 and unit will not accept programming changes

Safety first: Unplug the unit before opening the control housing.

Step-by-step checks:

• 1. Inspect keypad surface: Check for cracks, punctures, or signs of water damage on the Marlo keypad overlay. Sticky buttons or visible condensation indicate moisture intrusion.
• 2. Reseat ribbon cable: Remove the control cover and locate the ribbon cable connecting the display/keypad to the main board. Gently unplug and reinsert the cable, ensuring it is fully seated and not corroded.
• 3. Dry the panel: If moisture is present, allow the control to dry completely (24 hours in a dry environment). Do not use direct heat guns that could warp plastic.
• 4. Test button response: Restore power and attempt to enter programming mode. If some buttons work and others do not, the keypad membrane is likely failing.

When to replace parts: Replace the Marlo keypad/display assembly if buttons remain unresponsive. If a new keypad does not resolve Err7, the Marlo control board may need replacement.