82143A printer repair

[Dreato]

I'm repairing an 82143A printer using the service manual I found online. While going through some basic troubleshooting, I began to suspect that my printer is a newer version than the one in the service manual. For example, the main logic board in the manual is part # 821543-60009. My board is 82143-60035, The processor chip in the manual is 1820-2280. Mine is 1820-2314. There are other differences, too. My processor board incorporates a printer carriage home switch optical interrupter circuit - the older model has a mechanical home microswitch. The encoder detector is on the newer motherboard, too.

Has anyone else encountered this? Anywhere I can get the newer service manual, or the schematic for the newer board?

Thanks in advance for any help.

Regards,
Dave