Purpose

This article covers removal of an existing Castles UPT1000F reader and installation of an S1U2-M4 on MM6 and MM6 Mini kiosks.
 

Process

Prerequisites

1. Confirm the retrofit kit and required materials are available.
    
2. Confirm the replacement S1U2-M4, the model-specific retrofit bracket, spacer, bezel, and shipped harness are available for the kiosk model being serviced.
    
3. Confirm drivers or hex keys, cable labels, a camera or phone for teardown photos, ESD-safe handling practices, and a clean place to set the removed UPT1000F are available.
    
4. Confirm any optional 4G antenna kit is available, only if the site requires it.
    

Area Preparation

1. Take clear front and rear photos of the installed reader, mounting hardware, bracket, and every cable landing before unplugging anything.
   1. MM6: Capture the wider MM6 service area so you have a record of cable dress and any nearby printer or accessory wiring.
       
   2. MM6 Mini: For a Mini, document whether the kiosk is counter or wall mounted because the reassembly path can differ.
       
2. Record the old reader serial number and any site identifiers required.
    
3. Confirm the replacement S1U2-M4 serial number is documented for configuration by Support.
    

Kiosk Preparation

1. Shut the kiosk down.
    
2. Remove power before disconnecting the existing reader.
    
3. Open the kiosk door so the reader hardware and harness can be reached without stressing nearby components.
    
4. Do not begin removing the old reader until stable access and sufficient support for the front panel or bracket are in place.
   1. MM6: use the larger service opening and avoid dragging harnesses across the printer or other internal hardware.
       
   2. MM6 Mini: For wall builds, make sure the unit is supported and that the wall bracket is not carrying the full reader-removal load.
       

Removing the Old Reader

1. Label each cable before disconnecting it so the old path can be compared against the retrofit kit.
    
2. Remove the UPT1000F and any old bezel or bracket hardware that is not reused by the new kit.
    
3. Set the removed terminal aside in a protected area with its serial number visible or written down.
   1. MM6:  use the available space to label and stage the old harness before removal.
       
   2. MM6 Mini: work slowly so cables are not scraped or sharply bent while the old reader is removed.
       

Confirm Bracket

1. Test-fit the model-specific bracket or spacer before making final cable connections.
    
2. Confirm the S1U2-M4 sits square in the opening. Utilize the longer threaded holes on the bracket to attach the reader.
    
   
3. Confirm the terminal face is oriented correctly and that the bezel does not pinch cables or interfere with the kiosk housing.
    
4. Do not improvise the mount if the parts do not line up. [Stop and verify the kit.]
   1. MM6: confirm the larger front face still closes cleanly with the new bracket installed.
       
   2. MM6 Mini: confirm the bracket does not interfere with mount hardware or restrict the rear cable path.
       

Connect Cabling

1. Plug in the provided harness cables exactly as the retrofit kit specifies for the build. Do not assume the old UPT1000F cable positions map directly to the S1U2-M4.
   
   
   
   1. MM6: ensure the harness clears the chassis when closed.
       
   2. MM6 Mini: leave enough slack for service without allowing the harness to bunch behind the terminal.
       
2. Add the antenna only if the site build uses a cellular option and the antenna is included and specified for that kit.
    

Attach New Reader

1. Tighten the bracket and bezel hardware after connections are in place. Utilize the silver threaded holes on the bezel to attach the bezel and reader to the kiosk.
    
2. Confirm the S1U2-M4 sits flush and stable.
    
   
3. Secure the harness so it is protected from moving parts, sharp edges, and pinch points using cable ties or zip ties.
   1. MM6: confirm the harness stays clear of the service opening and any printer path or accessory wiring.
       
   2. MM6 Mini: confirm the rear cover or bracket can close completely without compressing the harness.
       
4. Re-check every fastener before closing the kiosk.
    

Test Reader

1. Plug in power and power up the kiosk.
    
2. Call Support and provide the new and old reader serial numbers.
    
3. Run chip, tap, and any other enabled payment tests.
    
4. Confirm the kiosk and terminal communicate cleanly.
   1. MM6: for builds that use receipts, include receipt-print validation in the post-retrofit test set.
       
   2. MM6 Mini: for wall mounted builds, complete a stability check so the mounted unit does not move during customer use.
       

Final Checklist

1. Confirm the old reader serial number is documented and provided to Support.
    
2. Confirm the new S1U2-M4 serial number is documented and provided to Support.
    
3. Confirm the correct model-specific bracket, bezel, and spacer are installed.
    
4. Confirm the harness is secured and free of pinch points.
    
5. Confirm the kiosk closes cleanly and the reader sits flush.
    
6. Confirm chip and tap tests pass, and confirm any enabled swipe or receipt functions are also validated.
    
7. Save final photos.