# Home position detection failure

1

LED lighting check of the SCN CIS module

• Check Method: Visually confirm that the LED turns on multiple times when the SCN carriage operates after powering on.
• Judgment Method: Check whether the LED on the CIS module is illuminating.

Go to step 3

Go to step 2

Check for disconnection or partial insertion of the SCN CIS module FFC connector.

• Check Location: SCN Board – CN602
• Judgment Method: Confirm whether the connector is disconnected or partially inserted.

If reconnecting the connector resolves the issue: End.

If reconnecting does not resolve the issue: Proceed to Step 3.

SCN CIS Module / SCN CR Installation Check

• Check Method: Confirm that the FFC is properly connected to the CIS module. Confirm that the CIS module shaft is properly installed onto the CR.
• Judgment Method: Confirm whether the error still occurs even when the CIS module and CR are installed correctly.

Go to step 4

End

SCN Upper Case – Condition Check

• Check Method: Confirm that there is no contamination or debris adhered near the home‑position pattern located on the SCN‑glass side of the SCN Upper Case.
• Judgment Method: Check whether the error still occurs after cleaning the contamination or replacing the SCN Upper Case.

Replace the SCN CIS Module

• Judgment Method: Does the error still occur after replacing the CIS Module?

Replace the SCN Board

• Judgment Method: Does the error still occur after replacing the SCN Board?

Replace the ADF/SCN Unit

• Judgment Method: Does the error still occur after replacing the ADF/SCN Unit?