Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to DC Volts 
Gain access to PCB (use Insulation Mat as required)
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Test 1.
Measure for DC voltage across pin 40 of connector CN2 & and pin 4 of connector CN4.
Make a note of the voltage reading.
Test 2.
Add some pressure to the system, then repeat test one.
Has the voltage increased from the reading obtained in test 1?
Measure for DC voltage across pin 40 of connector CN2 & and pin 4 of connector CN4.
Make a note of the voltage reading.
Test 2.
Add some pressure to the system, then repeat test one.
Has the voltage increased from the reading obtained in test 1?
Isolate as per TOPs P4
and refit as necessary