Bosch WAT28400 Repair Instructions page 35

Fault diagnosis
Fault
2017-05-22 / DIS 113_58300000186503_ara_en_c
Possible cause
Earth fault/short-circuit in heater.
NTC is interrupted.
NTC supplies incorrect measured values.
(For measured values of NTC see circuit
diagrams)
Earth fault/short-circuit in NTC.
Water level sensor interrupted.
Cable harness is interrupted.
Module defective (heater relay is hanging,
undervoltage, ...).
Component on module has become unsol-
dered.
Copyright by BSH Hausgeräte GmbH
Troubleshooting
► Replace heater.
► Advise customer:
The detergent dosage must always be dispensed as described in the instructions.
Not just 30 °C programmes should be selected, but also programmes with higher
temperatures.
This fault can be avoided if the appliance is occasionally treated with machine
cleaner [ 00311610] .
► Check NTC. (Page 51)
► Replace defective NTC.
► replace NTC.
► Replace water level sensor.
► Repair interruption in wire with connector.
► Replace interrupted wire in the cable harness.
► Replace cable harness.
► Replace module.
► Replace module.
Page 35 of 85