Si10-417
Troubleshooting
Service Diagnosis
163
5.4.11 Capacitor Voltage Check
Check
No.12
Checking the capacitor voltage
z
With the circuit breaker still on, measure the voltage at
the power transistor (+) and (-) terminals. Set the
multi-tester to DC and VOLTAGE RANGE before
measurement. Be careful never to touch any live
parts.
* Since capacitor (+) and (-) are connected to power
transistor (+) and (-), capacitor voltage can be
measured at the power transistor (+) and (-) terminals.
5.4.12 Power Transistor Check
Check
No.13
Checking the power transistor
z
Never touch any live parts for at least 10 minutes after
turning off the circuit breaker.
z
If you cannot avoid to touch a live part, make sure that
the power transistor's supply voltage is below 50 V
using the tester.
z
For the UVW, make measurements at the Faston
terminal on the board or the relay connector.
Tester's
negative
terminal
Power
transistor
(+)
UVW
Power
transistor
(–)
UVW
Tester's
positive
terminal
UVW
Power
transistor
(+)
UVW
Power
transistor
(–)
Normal
resistance
Several k
Ω
to several M
Ω
Abnormal
resistance
0 or
∞
Si10-417.fm Page 163 Wednesday, September 22, 2004 6:38 PM
