Service manual

QMS 3260/4032 Laser Printer - Base Engine Technical Manual 4-5
Release Version 11-97
Primary Fault Isolation Procedures
4.2 Erratic Operation
The printer has a variety of intermittent problems, but generally does not complete a print cycle. The prob-
lems are generally not identified by displayed Error Codes.
Step Actions and Questions Yes No
SUSPECT COMPONENTS
The followin
g
components are associated with this specific
problem. One or more of these components ma
y
have failed
partiall
y
or completel
y
. If
y
ou cannot isolate the problem usin
g
this FIP, replace each component listed below, one at a time,
until the problem disappears.
• Printer options
1
Does the printer frequently fail to enter printer warm-up or
is the Control Panel frequently inoperative?
Go to FIP 4.1
Inoperative
Printer
Go to step 2
2
LVPS +5VDC UNDER LOAD CHECK
1. Remove the Rear Cover (RRP 1.3)
2. Generate 50 Grid Test Patterns.
3. While the printing is generating the Test Patterns, measure
the voltage between J400-7 and FG on the MCU PWB.
Does the +5VDC measured between J400-7 and FG remain
relatively constant throughout the print run, and does not
deviate more than a volt during the print run?
Go to step 3 Replace the
LVPS Assem-
bl
y
(
RRP 9.2
)
3
LVPS +24VDC UNDER LOAD CHECK
1. Generate 50 Grid Test Patterns.
2. While the printing is generating the Test Patterns, measure
the voltage between J400-5 and FG on the MCU PWB.
Does the +24VDC measured between J400-5 and FG
remain relatively constant throughout the print run, and
does not deviate more than a few volts during the print
run?
Go to step 4 Replace the
LVPS Assem-
bl
y
(
RRP 9.2
)
4
TEST PRINT CHECK
Was the
p
rinter able to
g
enerate all of the Test Prints
re
q
uested in ste
p
s 2 and 3?
Go to step 5 Replace the
MCU PWB
(RRP 9.7)
5
TEST PRINT CHECK
Does the printer stop and reset while making test prints?
Go to FIP 6.1
Electrical
Noise
Go to step 6