Fault Code F78: Circulation Pump Fault - Miele G 4205 Technical Information

Technical Information
Note:
Upon opening the appliance and removing all water, there should be no
smudges, smears or traces of deposits. Take pictures of any deposits, if
possible, and note their type (rust, calcium, detergent, or salt).
2. Check all hoses, connections and threaded unions for leaks.
Note:
If the leak source has not yet been detected, check the following areas
in the toekick and the drip pan for wear and tear:
 Connection between the circulation pump and the sump
Axial face seal of the circulation pump

 Connection between the drain pump and the sump
 Connection between the salt container and the water intake
 Connection between the water intake and the cabinet side wall
 Overflow (e.g., excess foam formation)
 Water level between the overflows (seating of the lower door seal)
Connection between the cabinet and the salt container

 Non-return valve in the sump (water running back from the drain hose)
3. Check overflow float switch B8/3 for continuity and correct operation.
4. Carefully dry all electrical components in the drip pan area.
Cause:
Float switch defective.
Remedy:
Replace overflow float switch B8/3 (Section 050-4.19).
Cause:
Drip pan warped after transport.
Remedy:
Remove the drip pan. Bend it straight or replace if necessary (Section 010-4.2).
3.34

Fault Code F78: Circulation Pump Fault

Symptom:
The program is interrupted and the drain pump is operated.
Cause:
Interrupted connection between the electronic and the door contact switch.
Remedy:
1. Check for supply voltage.
a. Measure the voltage at the electronic (SLT) output and input.
b. Measure the voltage at the wiring harness.
c. Measure the voltage at the circulation pump.
2. Carry out appropriate remedial action (replacement of the electronic,
wiring harness or circulation pump).
Cause:
Faulty circulation pump (low or excess voltage, blocked, etc.).
146
G 5xxx