Dometic CT4000 Series
Official technical documentation and workshop diagnostics for Dometic CT4000 Series.
Technical Specifications
ElectricalDisplay input voltage: 12V DC / 0.03A constant power supply
Gas Or PressureNot applicable
Capacities DimensionsDimensions (W x H x D): 570 mm x 491 mm x 390 mm; Weight: 5.1 kg; Liquid Tank Capacity: 6.7 L; Solid Waste Container Capacity: 7.7 L; Urine hose inner diameter (Di): 10 mm; Ventilation hose inner diameter (Di): 6 mm
Master Troubleshooting & Diagnostics Matrix
| Error Code / Indicator | Symptom / Meaning | Step-by-Step DIY Fix | Suggested Actions |
|---|---|---|---|
N/A | Odor and moisture problems due to insfficient liquid drainage Possible Cause: Sharp bends, kinks, or improper slope in the drain hose | Route the drain hose without sharp bends or kinks, ensure proper downward slope using the hose gradient clamp, and make sure only liquids enter the front funnel area. | DIY Safe |
N/A | Level indication failure or error in tank status reporting Possible Cause: Connection cable pinched during separation cassette insertion | Route the level indication cable securely along the housing to the rear insertion side so it does not get pinched, and ensure the magnetic connector is correctly plugged into the cassette port. | DIY Safe |
N/A | Separation cassette does not snap securely into place Possible Cause: Locking part misaligned or locking pin missing from the base plate | Align the locking part with the 6.5 mm drill hole (located 63 mm from the front edge of the base plate) and insert the locking pin from underneath. | DIY Safe |
N/A | Toilet is clogged Possible Cause: Use of conventional toilet paper | Use quickly soluble toilet paper (Dometic COMFORT CARE recommended). | DIY Safe |
N/A | Unpleasant smells or poor waste decomposition Possible Cause: Missing or improper sanitary additives in the cassette tank | Use sanitary additives in the cassette tank (Dometic POWER CARE TABS or GREEN CARE TABS recommended) following manufacturer instructions. | DIY Safe |
N/A | Water pipes or tanks frozen during winter Possible Cause: Toilet and cassette tank operated in sub-zero/frost areas without draining | Empty the cassette tank, fresh water tank, and all water pipes if operating in areas prone to freezing. Do not use antifreeze. | DIY Safe |
N/A | Toilet clogged Possible Cause: Use of conventional non-soluble toilet paper | Use quickly soluble toilet paper (Dometic COMFORT CARE recommended). | DIY Safe |
N/A | Water pipes or tanks frozen / winter operation failure Possible Cause: Sub-zero temperatures in the toilet or cassette tank area | Ensure the area is frost-free. If freezing is possible, completely empty the cassette tank, fresh water tank, and all water pipes. | DIY Safe |
N/A | Toilet clogging Possible Cause: Use of conventional non-soluble toilet paper | Use quickly soluble toilet paper such as Dometic COMFORT CARE | DIY Safe |
N/A | Unpleasant odors / slow waste breakdown Possible Cause: Inadequate or missing sanitary additives in the cassette tank | Use recommended additives such as Dometic POWER CARE TABS or GREEN CARE TABS following manufacturer instructions | DIY Safe |
N/A | Water pipes or components freezing during winter storage Possible Cause: Residual water remaining in lines or tanks in sub-zero frost environments | Empty cassette tank, fresh water tank, and completely flush all water-carrying pipes using the flush button until completely empty | DIY Safe |
N/A | Unpleasant smells or poor waste decomposition in the cassette tank Possible Cause: Lack of proper sanitary additives or incorrect dosage | Use sanitary additives (Dometic POWER CARE TABS or Dometic GREEN CARE TABS) following manufacturer instructions | DIY Safe |
N/A | Water pipes or components frozen during winter operation Possible Cause: Freezing temperatures in unheated areas | Ensure toilet and cassette tank are used in frost-free areas; otherwise, completely empty cassette tank, fresh water tank, and all water pipes | DIY Safe |
N/A | Stiff mechanical movement or leaking seals Possible Cause: Lack of lubrication and build-up of residue on seals and moving parts | Clean and grease all seals and moving parts monthly or after every 3 to 5 emptyings using silicone-based grease or spray (OKS-1110 grease or OKS-1111 silicone grease recommended) | DIY Safe |