Miele G500 Technical Information page 104

Technical Information
5.5 Service Work on Models G595 and G598
Before setting out to locate a fault, the points listed below should be noted
in addition to all other valid safety regulations.
a) Program sequence
In order to check the program sequence of the EPW531, it is
important to know which additional functions have already been
programmed in. How to check the individual functions is described in
Section 6.1.1 – Programming Mode.
Other important service programs are in the service mode (refer to
Section 6.1.2), the program duration display mode (Section 6.1.2.3),
the component test program (Section 6.1.2.5) and the error message
mode (Section 6.1.2.1).
A valid wiring diagram for each machine can be found in the fascia
panel.
b) Test instrument and accessories
Checks on the electronic unit require a suitable test instrument with an
internal resistance of at least 20 kOhm/V.
All readings listed in this chapter were taken using a Metrawatt M
2030 multimeter. Tolerances of ± 10% due to variations in the mains
supply, individual components and test procedures are both likely and
acceptable.
A set of long, thin test prods should be used and are available under
Part no. A 9976 (red) and Part no. 9990 (black).
c) Checking the mains potential
In order to avoid incorrect readings, it is important to first define a
reference datum for all subsequent measurements. When working
from a mains supply, the reference point is generally taken to be the
neutral conductor.
L1, L2, L3
N
d) Checking the extra-low voltage circuit
Low voltages should not be measured against the mass of the casing,
earth or the neutral conductor (N)! Only the contacts expressly
mentioned should be used fro the purpose of taking readings.
GND
U
U+
Mains Voltage
Neutral
Note all valid regulations regarding earthing!
Reference datum
Alternating current
Positive direct current
104
G500 Dishwashers