Xerox 790 Error message

[davidlakey]

I have a Xerox 790, dislpaying the error message 006-372. Can anyone please advise me as to the meaning of this, and or possible soloution(s).

 

[gudz90]

006-372 Start of Scan Error RAP

During or after warm-up, the Start of Scan (SOS) signal is longer than specified.

Procedure

Switch off the power. Remove the IOT Top Cover Assembly (REP 14.4). Remove the Controller
Chassis (REP 1.11). Switch on the power. Cheat the Top Cover Interlock. Approximately
+4 VDC is measured between J 14-11 and J14-10 on the MCU PWB.
YN

Go to Flag 1 and check the wire for a short circuit to ground. If the wire is good, replace

the MCU PWB (PL 11.2).

+24 VDC is measured between J 14-13 and J14-10 on the MCU PWB.
YN

Replace the MCU PWB (PL 11.2).

Switch off the power. Remove the ROS Cover. Disconnect J 123 from the ROS. Measure the
resistance between the following plug/jack pins:

• P/J 14-11 on the MCU PWB to J123-3
• P/J14-13 on the MCU PWB to J123-1
• P/J14-12 on the MCU PWB to J123-2
• P/J14-10 on the MCU PWB to J123-4
All the measurements are less than 1.0 Ohm.
YN

Go to Flag 1 and Flag 2. Check the wires for an open circuit.

Reconnect J 123. Switch on the power. +5 VDC is measured at J 125-1 on the ROS.
YN

Go to the 001-705 ROS +5 VDC Switched Voltage RAP.

Switch off the power. Disconnect J 121 from the ROS. Measure the resistance between the following
plug/jack pins:

• J 14-5 on the MCU PWB to J121-3
• J14-4 on the MCU PWB to J121-4
• J14-7 on the MCU PWB to J121-1
All measurements are less than 1.0 Ohm.
YN

Go to Flag 3 and check the wires for an open or short circuit.

Replace the ROS (PL 5.1). If the problem continues, replace the MCU PWB (PL 11.2).

Initial Issue 10/00 Status Indicator RAPs
Phaser 790/DocuColor 2006 2-73 006-372