Service manual

7020
c. Press [Next] several times until the display reads [HV adj (L detection adj)].
d. Press [Start].
e. When the adjustment is complete, the machine will stop and a value is displayed in [RESULT].
f. If the developer was sampled properly during the L-detect adjustment, the value displayed in
[RESULT] will be in the 60-75 range.
g. If the L-detect adjustment [RESULT] value is outside of the 60-75 range, than the TDS (toner
density sensor) should be checked.
2. Failed TDS (toner density sensor). To check the TDS, perform the following:
a. Remove the IP unit (if an IP unit is installed).
b. Remove the rear and left rear side cover.
c. Remove the board cover/D (p/n 26NA73280) for access to the PRDB.
d. Enter the 36 mode (turn the machine ON, while pressing the 3 and 6 keys).
e. Select [1. HV adjustment].
f. Press [NEXT] several times until the display reads [HV adj. (Toner auto supply)].
g. Locate TP14 (TDS AN) in the middle of the PRDB above CN 25.
h. Using a voltmeter (20V DC range), place the red meter lead on TP14 and the black meter lead
to frame ground.
i. Press the START button on the control panel.
j. The analog voltage reading on the volt meter during sampling should be (with properly toned
developer) between 1.2 and 2.0VDC. If the voltage reaches 2.0VDC, M4 (toner addition motor) will
turn on and add toner. When the toner auto supply adjustment is finished the voltage should read
approximately 1.8VDC.
k. If the voltage reading is not within this range, replace the developer (PCUA 950237), TDS (p/n
26NA88040) and run the l-detect adjustment while monitoring TP14 on the PRDB.
3. Failed write unit (the TCSB monitors dot pattern patches created on the drum and adjusts the
laser output for Maximum Power Control). If developer has been replaced, L-detect run, the TDS
voltage checks, and the developer is still overtoning (M4 continuously adds toner), replace the write
unit (p/n 26NA-6503).
Blank display, data light on only.DESCRIPTION: SOLUTION ID:
86006
SOLUTION:
CAUSE: Operation instruction not loaded.
SOLUTION: ROM levels needs to be flashed.
USAGE:
6
Blur/streaks on copies.DESCRIPTION: SOLUTION ID:
90577
SOLUTION:
CAUSE: Exposure unit (1st mirror frame) is out of alignment.
SOLUTION: Re-align the exposure unit (1st mirror frame).
Notes:
1. Refer to page 3-8 of the 7020 service manual (March 2000).
2. Be sure to use the optics-positioning jig (p/n 26NAJG011) when re-installing or adjusting the
exposure unit (1st mirror frame).
3. Copy quality will be fine with internal test patterns.
4. [[Hyperlink to sample of copy quality problem| IMAGE V:\bitmaps\cjc268.bmp SCROLL]].
USAGE:
6
Recommended transparency, 7020.DESCRIPTION: SOLUTION ID:
94917
SOLUTION:
The standard Konica transparency (PCUA 946427) is recommended. This transparency is
equivalent to the 3M* type PP2500 (688/503).
*[[Trademark ownership information| FILE V:\TEXT\TRADEMRK.TXT NEW]]
USAGE:
6
DF314, dark line from lead to trail.DESCRIPTION: SOLUTION ID:
98567
SOLUTION:
CAUSE: Failed A/D conversion board.
SOLUTION: Ensure that the scanner slit glass is cleaned and free from contamination. Reseat the
connectors on the control board (CN46) and on the A/D conversion board. If problem persists,
replace the CCD unit (p/n 26NA-6260).
USAGE:
6
The machine does not recognize inch size paper.DESCRIPTION: SOLUTION ID:
99960
SOLUTION:
CAUSE: The Destination switch was not set for USA.
SOLUTION: To set the destination switch for USA, perform the following:
1. Access the 25 mode (power the machine ON while holding down on the 2 and 5 keys).
2. Press 1 on the touch screen (Software SW).
3. Scroll to switch 5-0 using the arrow keys on the touch pad.
4. Press the ON button to change the data to a 1.
USAGE:
6
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Copyright 2005, Konica Minolta Business Solutions U.S.A., Inc.
May 2005