Dometic Control Module 12/24VDC (DBL) 385880085 for Masterflush Toilets

Dometic Control Module 12/24VDC (DBL) – 385880085

Electronic Dual-Voltage Control Module for Dometic MasterFlush Toilets

When the flush system on your RV or marine toilet becomes inconsistent, unreliable, or unresponsive, the Dometic 385880085 Dual-Voltage Control Module ensures proper flushing operation. Designed for 12 V and 24 V MasterFlush models (including 8600, 8700, 8900 series), this OEM control module manages motor power, water valve activation, and electrical timing, restoring reliable performance and safety.

Features & Benefits

• OEM dual-voltage (12 V / 24 V DC) control module for MasterFlush toilets
• Manages motor and water-valve activation to ensure proper flush cycles
• Compatible with most MasterFlush models (8600, 8700, 8900)
• Replaces worn or faulty factory electronics to restore reliable flushing
• Plug-and-play replacement—no complex wiring modifications needed
• Helps prevent motor burnout and ensures correct valve sequencing

Compatible Models

Worked with:

• MasterFlush 8600 (low and tall)
• MasterFlush 8700 (tall)
• MasterFlush 8900 (low and tall)

Makes a good replacement for 12 V or 24 V MasterFlush systems using double-voltage control configurations.

Common Issues Solved

Installing the 385880085 module can resolve:

• Vacillating or weak flush cycles
• Flush motor not starting or cutting out mid-cycle
• Water valve not activating or remaining open after flush
• Intermittent flush operation or flush button failure
• Burned-out electronics causing system failure

Replaces / Also Known As

• Dometic 385880085 Control Module
• MasterFlush Dual-Voltage Electrical Module
• MasterFlush 12/24 V Flush Control Box
• Replacement ECU for Dometic Macerator Toilets

What’s Included

• 1 Dual-voltage control module unit (12 V / 24 V)
• Wiring connectors compatible with standard MasterFlush wiring harnesses

• Installation Overview
• Disconnect power to your toilet’s electrical circuit (battery or distribution panel).
• Open the toilet’s access panel to locate the existing control module.
• Disconnect wiring harness and remove old module.
• Connect new 385880085 module to the existing harness (plug-in style).
• Restore power and test flush cycle to ensure correct operation.

Typical installation time: 5–15 minutes — no soldering or wiring changes required.

Frequently Asked Questions

Q: How do I know if my MasterFlush needs a new control module?
If the flush motor doesn’t run, cuts out during flush, or the water valve doesn’t activate properly — often the control module is the culprit.

Q: Will this work with both 12 V and 24 V systems?
Yes — the 385880085 is rated for both 12 V and 24 V DC MasterFlush installations.

Q: Is any rewiring needed for replacement?
No. The control module is a direct plug-and-play replacement using existing wiring harness.

Q: Does this fix water valve issues too?
Yes — since the module controls flush motor and water valve activation. If water flow was erratic due to electrical issues, this often resolves it.

Q: Is this an OEM part?
Yes — 385880085 is the official factory control module for MasterFlush toilets.