Print Quality Switch

Print quality switch allows the user to choose one of three printing modes. Pressing the print quality switch repeatedly changes the mode from the standard print mode, to the NLQ print mode, to the draft print mode, back to the standard print mode again. The print quality switch does not function unless the printer is in an off-line (deselected) state. Form Feed - The form feed switch does not function unless the printer is in an off-line (deselected) state. When the form feed switch is...

Carrier Assembly Top Plate

Caution Review the ESD precautions in Bulletins Safety. 1 Caution Do not use force when you remove the black plastic arms. You will break them. Using a small flat-blade screwdriver, push out the black bearing arm. 2 With another small screwdriver, gently pry the arm upward at a slight angle. 3 Move the small arm to the top. 4 Gently pull the plastic bearing straight out and remove the small washer.

Ribbon

Imagewriter Printout

No preliminary steps are required before you begin this procedure. Caution Review the ESD precautions in Bulletins Safety. Note Perform the ribbon cam adjustment when the color print function fails, when you replace the color ribbon, when dots are missing, or when no printout appears when you use a black ribbon. 1 Run the self-test. See Additional Procedures. Note If you use a color ribbon, the self-test should produce one line of each color (black, yellow, red, blue, orange, green, and purple)...

Color Ribbon Detect Switch

1 Note Do not bend the plastic tabs that hold the wires. Carefully pry the wires out of the embedded track of the top plate. Turn over the top plate. Using a small screwdriver, gently pry the four latches and at the same time push down on the bottom of the switch so the switch comes out from the top of the plate.

Carriage Movement

Carriage assembly moves to the left and does not return to center 1 Verify operation of switch on print head board. If switch is frozen or defective, replace print head board. 2 Verify that metal tab actuating left-side home position switch is bent correctly. Use a feeler gauge and bend tab 1 mm toward right side. 5 Replace flexible ribbon cable. Carriage moves to the left and hums very loudly Verify that flexible ribbon cable is properly connected to main board and to its connector under...

Pinch Roller Assembly

1 Remove the two screws on the back of the pinch roller assembly. screwdriver, gently pry the roller assembly free from the five tabs. Pull up the front section of the pinch roller assembly until the assembly is loose and remove the connector CNS3 from the sub PCB interface board. Lift off the two pinch rollers and pinch roller springs. Push up on the small roller from underneath.

Operation Panel

Caution Review the ESD precautions in Bulletins Safety. Remove the three screws and lift the operation panel board from the top cover. Disconnect the cable from the operation panel board. Note To make reinstallation easier, observe the position of the power switch plunger and spring. Remove the spring and power switch plunger from the top cover. Perform the self-test. See the Additional Procedures chapter.

Top Cover

1 Push the carrier assembly to the far left. 3 Loosen the two captive screws. Grasp the top cover on the left at the part that goes over the leg. Release the latch and lift the cover one inch. 6 Gently rotate the cover toward the front and turn the cover over. 7 Using your thumb and forefinger, unlock connector CN7 and remove the ribbon cable.

Print Head Board

The print head board receives the print head drive signals from the main board through CNH1. The signals are then sent out on connector CNH2 to the print head. This board also handles the ribbon motor drive signals and the ribbon switch signals. If the switch is activated, a color ribbon is detected. This information is sent to the main board, which in turn sends controlling signals to the ribbon motor to control the position of the ribbon to allow color printing. The home position switch...

Preliminary Check

1 Verify that paper cover is secure. 2 Verify that paper cover magnet is in place. 4 Verify that option card dip switch SW2-4 is open off with no card installed. 1 Add paper or reset paper feed tray. 2 Verify that paper-out sensor works correctly (see Take Apart). 1 Verify that paper cover is secure. 2 Verify that paper cover magnet is in place. 3 Verify that operation cable under top cover is secure. Prints OK for a while then prints garbage 1 Check interface cable connection between printer...

Carrier Assembly

Printer Head Belts

Before you begin, remove the following Caution Review the ESD precautions in Bulletins Safety. Unhook the ribbon wire from both sides of the frame. Move the carrier assembly to the right so that the right edge of the carrier housing is lined up with the edge of the main board or the right edge of the platen. Lift the front edge of the carrier assembly and remove the carrier from the metal rail guide. 4 Using needlenose pliers, pry the metal finger toward the front of the printer.

Flexible Ribbon Cable

Flexible Ribbon Cable Guides

Before you begin, remove the following Caution Review the ESD precautions in Bulletins Safety. 1 Remove the ribbon cable from connector CN5 on the main board. 2 Move the carrier assembly toward the right side of the carrier until the assembly is lined up with the right edge of the board. Slightly lift up the front of the carrier assembly until you hear a snap. 4 Caution Do not force the flexible cable loose or you will damage the cable. Using a small screwdriver, gently turn the screwdriver...

Shims

Carrier Shaft

Caution Review the ESD precautions in Bulletins Safety. Note This procedure covers the gap check, and the installation and removal of the shims. Note Before performing the following procedures on shims, check the cam washer on the left side of the carrier shaft to be sure the washer is in position. The flat part of the hole in the cam should face the front of the printer when you place the cam on the carrier shaft. Refer to Carrier Assembly in the Take Apart...

Firing Hammer

No preliminary steps are required before you begin this procedure. Caution Review the ESD precautions in Bulletins Safety. Note Perform the firing hammer adjustment only when you replace the carrier belt, carrier shaft, carrier motor, or main board. 1 Print a few lines of the capital letter H. 2 Check the printed letters for misalignment. 3 Note Change only one switch at a time. If the letters are misaligned, remove the covers. Using a small screwdriver, change the settings of DIP switches 2-5...

Main Board

The main board is the heart of the printer. Besides handling the distribution of the voltages, it also handles all the logic that controls the printer. It is also the source of the drive signals for the print head. All sensor signals that affect the operation of the printer are fed to this board. The ROM IC1 0 chip has the start-up routines and several features such as character sets and self-test routines built in. The RAM IC9 is used in the transfer of data and acts as a buffer. When printing...

Ribbon Motor Drivers

This circuit is made up of transistors Q3, Q4, Q5, Q6 and Q.7. When turned on, the line feed motor signals from the gate array are supplied with more current in the drive circuit and sent out to the motor. The common return line is on Q7, which is turned on for each phase signal sent to the motor. These signals are sent through CN5. This circuit is used when the printer is turned on to keep the logic in a reset state until the voltages are up to correct values. Once the voltages are at the...