Nautilus SM916 Stepmill Troubleshooting and Serial Number Guide

SM916 14-Digit Serial Numbers

Nautilus SM916 serial numbers are 14 digits long. They are similar to the Stairmaster 2400PS Stepper serial numbers.

Example Serial Number: #14001071231001

The serial number is broken down as follows:

14001 | 07 | 12 | 31 | 001

A. Machine ID Number:

• 14001 = Domestic, 110V, Unboxed
• 14002 = Domestic, 110V, Boxed
• 14003 = International
• 14004 = Domestic, 110V, TV Ready, Unboxed
• 14002 = Domestic, 110V, TV Ready, Boxed (Note: Duplicate entry in source)

B. Year Machine Was Made: 07 = 2007

C. Month Machine Was Made: 12 = December

D. Day the Machine Was Made: 31 = 31st day of the month

E. Machine Number of the Work Order: 001 = 1st machine for work order #xxxxx

C51 & C52 Cardio Console Codes

General Information:

• To enter console modes, press the UP Speed/Load key [], the numeric [#] key, and then press the [ENTER] key.
• Pressing [] or [] navigates through selections. Pressing [ENTER] selects an item. Enter values and press [ENTER] to store.
• Pressing [CLEAR] exits special access modes. Pressing [CLEAR] twice exits Console Service Mode.

Workout Default Console Codes:

• [ ] [2] [ENTER] "DEFAULTS"
• [▲] [ENTER] "ENTER WT XXX"
• [▲] [ENTER] "ENTER LEVEL 1 TO XX"
• [▲] [ENTER] "ENTER TIME XX"
• [▲] [ENTER] "ENTER AGE XX"
• [▲] [ENTER] "CHR PERCENT XX"
• [▲] [ENTER] "ENTER SPEED XX.X" (TM, TC only)
• [▲] [ENTER] "QUICKSTART SPEED XX.X" (TM, TC only)
• [▲] [ENTER] "MIN INCLINE XX" (future)
• [ ] [3] [ENTER] "CUSTOMIZE"
• [▲] [ENTER] "MAX TIME"
• [▲] [ENTER] "COOL DOWN"
• [▲] [ENTER] "CHANGE UNITS"
• [▲] [ENTER] "HR INPUTS"
• [▲] [ENTER] "SELECT STATS" (T916 TM)
• [▲] [ENTER] "LANGUAGE"
• [▲] [ENTER] "CONTRAST UPPER"
• [▲] [ENTER] "CONTRAST LOWER"
• [▲] [ENTER] "MAX SPEED" (TM only)
• [▲] [ENTER] "ENABLE MAG KEY" (TM only)
• [▲] [ENTER] "AUTO STOP"
• [▲] [ENTER] "SET DEFAULTS"
• [ ] [4] [ENTER] "MACHINE STATUS"
• [▲] [ENTER] "RUN HOURS"
• [▲] [ENTER] "WORKOUTS"
• [▲] [ENTER] "DISTANCE"
• [▲] [ENTER] "CONSOLE VERSION"
• [▲] [ENTER] "DEVICE TYPE"
• [▲] [ENTER] "TM DRIVE VER" (Displays Machine Type) (TM only)
• [▲] [ENTER] "MAINT HOURS"
• [ ] [5] [ENTER] "RAND D"
• [▲] [ENTER] "PROGRAM LOOP"
• [▲] [ENTER] "COM TIME DISABLE"
• [ ] [6] [ENTER] "DIAGNOSTIC"
• [▲] [ENTER] "DISPLAY TEST"
• [▲] [ENTER] "KEY TEST"
• [▲] [ENTER] "SERIAL PORTS"
• [▲] [ENTER] "A SENSOR B"
• [▲] [ENTER] "I/O TEST"
• [▲] [ENTER] "ALT TEST" (Non-TM only)
• [▲] [ENTER] "TACH TEST" (Non-TM only)
• [▲] [ENTER] "BUS VOLTS" (TM, TC only)
• [▲] [ENTER] "TREADLE CENTERING" (TC only)
• [▲] [ENTER] "TREADCLIMBER" (TC only)
• [▲] [ENTER] "AUTO STOP" (TM only)
• [▲] [ENTER] "GRADE ACT" (TM only)
• [ ] [7] [ENTER] "SERVICE"
• [▲] [ENTER] "ERROR LOG"
• [▲] [ENTER] "MAINT HOURS"
• [▲] [ENTER] "QA ID"
• [ ] [8] [ENTER] "Machine Configuration" [ENTER]

For Non-Treadmill Devices, the selections are:

• [▲] [ENTER] "TC/TM CONFIG RQD"
• [▲] [ENTER] "TREADCLIMBER"
• [▲] [ENTER] "T9.16" (T916)
• [▲] [ENTER] "T9.14" (T914)
• [▲] [ENTER] "NTM CONFIG RQD"
• [▲] [ENTER] "BIKE"
• [▲] [ENTER] "ELLIPTICAL"
• [▲] [ENTER] "STEP MILL"
• [▲] [ENTER] "STEPPER"

For Treadmill Devices, the selections are:

• [▲] [ENTER] "TC/TM CONFIG RQD"
• [▲] [ENTER] "TREADCLIMBER"
• [▲] [ENTER] "T9.16" (T916)
• [▲] [ENTER] "T9.14" (T914)
• [▲] [ENTER] "NTM CONFIG RQD"
• [▲] [ENTER] "BIKE"
• [▲] [ENTER] "ELLIPTICAL"
• [▲] [ENTER] "STEP MILL"
• [▲] [ENTER] "STEPPER"

(TC = TreadClimber, TM = Treadmill, NTM = Non Treadmill e.g., "BIKE", "ELLIPTICAL")

©2005. Nautilus, Inc. All rights reserved. Nautilus and the Nautilus logo are either registered trademarks or trademarks of Nautilus, Inc.

Part Number 26443A

Troubleshooting Guide for Alternators on Stepmills

Product: Nautilus Step Mills

Date: June 3, 2008

Distributed By: Gary Pendleton

This guide addresses intermittent or no resistance issues on Nautilus Step Mills, often solved by replacing alternator brushes or the alternator itself. Nautilus requests failed alternators be returned for analysis.

1. No Resistance When Stepping

• Remove the right side panel to view the Relay board LEDs.
• Begin moving the staircase.
• If all three LEDs on the relay board are lit but there is no resistance: Replace Alternator brushes or Alternator.

2. Intermittent Resistance

• Begin moving the staircase.
• Staircase grabs at high speed only and Field LED lights momentarily then goes out: Replace Load resistor.

3. No Resistance and No Field Light

• Begin moving the staircase.
• Staircase freewheels and Field LED doesn't light.
• Perform Tach test by entering diagnostics.
• If there is no Tach signal sensed on console:
  • Check for 0.6 to 0.7 volts AC at the W-4 (Tach) terminal of the alternator.
  • If no voltage, remove the blue Tach wire from the alternator while the staircase is moving.
  • Touch the Tach wire to the Field terminal.
  • If the Field LED lights, Replace the alternator.
  • If the voltage checks good, remove the blue connector from the W-4 (Tach) terminal of the alternator. Lightly scrape the connector and re-install. Re-check.
  • If still bad, replace the console.

Diagram: Alternator Wiring and Relay Assembly

Visual representation of the alternator connections (W-4 Tach, W-5 Output, W-6 Ground, W-3 Field) and the Relay/Resistor Assembly. Shows connections like W-2 (Black), W-1 (White), W-5 (White), W-6 (Black), W-3 (Brown), W-4 (Tach). The Relay Assembly shows terminals for Power, Field, Tach, RES, and Ground.

4. Staircase has Resistance but Freewheels when Quick Start or Program is Entered

• Replace console.

5. Staircase has resistance but is choppy during exercise

• Inspect Main Cable for Corrosion at all connections.
• Check Load Resistor for a reading of 0.5-0.6 Ohms.
• Replace alternator brushes or alternator.

6. Relay Board Tests

• Disconnect the main cable from relay board J1 terminal.
• With power on, place jumper across GND/BLK and RLY/RED test points: Relay LED should light.
• With power on, place jumper across +/WHT and FLD/BRN test points: Field LED should light.
• With power on, place jumper on +/WHT and with the other end touch the ALT/C, FLD/NC, and RES/NO: Field LED should light.
• If any of these jumps fail, replace relay board and/or power supply.

Diagram: Relay Board Test Points

Illustration showing the Relay Board with labeled test points: Power Connector Socket, Main Cable Socket. Test points include GND/BLK, RLY/RED, +/WHT, FLD/BRN, ALT/C, FLD/NC, RES/NO. It also shows the Relay Assembly with numbered terminals.

7. Other Points

• The Field LED on the relay board requires a Tach Signal on the blue wire for the console to activate field current to the alternator (PWM controlled).
• If the alternator is suspected, disconnect wires and check resistance across the field terminal and alternator housing (typical Prestolite Alternator: ~4 Ohms).
• The Field LED may flicker at higher speeds, indicating the PWM signal controlling resistance/speed. If full resistance is present and the light doesn't flicker, replace the console.
• Always perform mechanical troubleshooting in addition to electrical troubleshooting for resistance problems.

8. Alternator Return Instructions

Note: The following return instructions are marked as "NO LONGER APPLIES after Sportsmith becoming support center. 6/24/10 ss mkl".

Failed alternators were to be returned to:

Joe Polaro
Southeast Service Manager/
Field Quality & Reliability Specialist
55 Westwood Drive
Ruckersville, Virginia 22968

Instructions included including the Step Mill Serial Number, miles, hours, failure symptoms, and shipping the complete alternator (do not remove brushes) via UPS using account number 7R4A03.

SM916 Electrical Troubleshooting Flowcharts

The following describes the troubleshooting flowcharts for SM916 electrical issues.

Flowchart 1: Initial Electrical Testing

Start: Perform general SM916 electrical testing.

Confirm external power supply is installed in a live outlet and plugged in.

Decision: Does the console turn on?

[No] <-> Perform Alternator / Resistance Testing.

[Yes] <-> Step onto the staircase.

Decision: Is stiff resistance felt?

[No] <-> Perform Alternator / Resistance Testing.

[Yes] <-> On the console, press "Quick Start" to enter a manual workout.

Decision: Is an increase in step rate felt?

[No] <-> Perform Alternator / Resistance Testing.

[Yes] <-> (Proceed to next flowchart section, indicated by '2').

Intermediate Step: Remove 4 screws holding console to mast.

Carefully tip console forward and measure voltage from pins 1 and 10 of interface connector.

Decision: Is Voltage 10V or Greater?

[No] <-> Replace console.

[Yes] <-> Perform Voltage Testing.

Flowchart 2: Step Rate and Voltage Testing

Continuation from Flowchart 1 (indicated by '2'):

Decision: Does the step rate feel smooth?

[No] <-> Perform Alternator / Resistance Testing.

[Yes] <-> Increase levels to increase step rate.

Decision: Does Step rate Increase?

[No] <-> Perform Alternator / Resistance Testing.

[Yes] <-> Stop climbing, and press stop twice if workout results are desired.

End State: SM916 Is Operating Properly!

Flowchart 3: Voltage Testing Details

Start: Perform Voltage Testing.

Remove right side of machine's plastics referenced to the front of the staircase.

With a voltmeter, measure voltage from 23545 PCB's J2 pins 1 and 2.

Decision: Is Voltage 10V or more?

[No] <-> Measure voltage at power entry point of 21768 cable, pins 1 and 2.

[Yes] <-> Measure voltage on 23545's J1 pins 4 and 5.

Decision: Is Voltage 10V or more?

[No] <-> Replace 21768 cable.

[Yes] <-> Resolve continuity issue with interface cables leading to console, part numbers 21769 and 27831.

Decision (from measuring 21768 cable): Is Voltage 10V or more?

[No] <-> Replace 12V external power supply.

[Yes] <-> Replace 23545 PCB.

End State: Perform general SM916 electrical testing.