Troubleshooting

5.3 Repair of the C172 PSB/PSE Board at Component Level

This section contains information which enables you to repair and replace the components on the electrical board (C172 PSB/PSE). Table 5-5 lists the potential causes for each symptom in order of possibility, with which you are able to find and repair the defective part.

Table 5-5. Component Repair of the C172 PSB/PSE Board

Symptom

Condition

CauseCheckpoint

Solution

 

 

 

 

 

 

 

 

 

The printer

+42 VDC is

Fuse (F1) is

Check visually if the fuse is good. Replace the fuse F1.

does not

not output.

open.

 

 

operate at all.

 

Transformer

Check the transformer using a

Replace the

 

 

(T1) is open.

multimeter.

transformer T1.

 

 

Q1 is dead.

Check the waveform at drain.

Replace the Q1.

 

Waveform (1)

Q2 or Q3 is

Check the waveform at corrector. Replace the Q2 or Q3.

dead.

 

 

 

 

Waveform (2)

PC1 is dead.

Check the voltage in lowering at Replace PC1.

 

the Pin 5 or 7.

 

 

 

 

 

Waveform (3)

+5 VDC is

L4962 is dead. Check the reference waveform Replace the L4962.

not output.

at the Pin 5.

Waveform (4)

Check the output waveform at the

Pin 7.

Waveform (5)

5-10

Rev. A