Tektronix Phaser 550 Service Manual page 134

6
Troubleshooting
6-20 Phaser 550 Color Printer
Table 6-2 Print engine service error codes (cont'd.)
Error code Meaning of error code and what to do about it
13 L-sync under.
1. Replace the engine control board.
2. Replace the laser scanner.
20 Charger error.
Scorotron charger
1. Ensure that the imaging unit is properly installed and locked in place.
2. Ensure the scorotron charger is properly installed. Ensure the
charger is clean with no foreign matter in the area. Also ensure the
wire and grid plate are in good condition.
3. Inspect the wiring leading from the high voltage board to the scoroton
charger.
4. Replace the scorotron charger if necessary.
5. Replace the imaging unit.
6. Replace the high-voltage board.
First bias transfer roller
1. Ensure that the imaging unit is properly installed and locked in place.
2. Inspect the wiring leading from the high voltage board to the imaging
unit.
3. Replace the imaging unit.
4. Replace the high-voltage board.
Second bias transfer roller
1. Ensure that the paper feeder is properly installed and locked in
place.
2. Ensure the transfer roller is properly installed. Ensure the bias roller
makes good contact with its electrical contacts.
3. Inspect the wiring leading from the paper feeder to CN309 of the
engine driver board.
4. Inspect the wiring leading from the high voltage board to the second
bias transfer roller.
5. Replace the high-voltage board.
Toner cartridge bias
1. Ensure that each toner cartridge makes good electrical contact with
its high voltage bias terminals.
2. Inspect the wiring leading from the high voltage board to the toner
cartridge bias terminals.
3. Replace the toner cartridge if a single cartridge is exhibiting trouble.
4. Replace the high-voltage board.
5. Too much conductive grease on the high-voltage contacts of a toner
cartridge developer toller has migrated down and shorted to the
chassis. Conductive grease should be used very sparingly.
21 Photoconductive belt out of sync with accumulator belt.
1. Ensure that the imaging unit is properly installed and lock in place.
2. Inspect and clean the transparent plastic cover over the accumulator
belt position sensor.
3. Inspect the wiring harness leading from the accumulator belt
position sensor to CN13 of the engine control board.
4. Replace the imaging unit.
5. Replace the accumulator belt position sensor.
6. Replace the engine control board.