Maestria / Gran Maestria service manual
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F U N C T I O N T E S T S
9.10.4 What to do if the insulation test fails
•
Assume that the coffee machine is defect after a failed insulation test.
•
Check wiring and locate fault. After fault clearance proceed with troubleshooting
check list (see see “Troubleshooting” on page 34).
•
In case of doubt an insulation test on the milk frother alone can be carried out on the
coffee machine Gran Maestria EF 287: touch phase and neutral contacts at the
bottom with one test probe successively and the outside of the metallic jug with the
other test probe.
If insulation test fails, replace milk frother.
Risk of damage!
A sparkover can damage the electronic control board and sensors etc.