Tip & How-To about Stairmaster 4600 Cl Cordless Freeclimber
Load Resistor Testing for 4400CL and 4600CL Steppers
This video covers troubleshooting of the load resistor on the Stairmaster 4400CL and 4600CL Steppers.Tools Needed: Multi Meter
The load resistor is cylindrical in shape and has metal fins encased in the ceramic coating around the outside. The job of the load resistor is to take the extra electricity from the alternator and dissipate it as heat. Symptoms that one may experience when the load resistor fails are alternating resistance in the pedals or no resistance in the pedals. Alternating resistance can occur as the load resistor heats or cools causing the resistance to come and go. If the load resistor is really bad, there can be no resistance in the pedals.
You can test the load resistor by first following the wires from the load resistor to the lower control board.
Next, carefully disconnect the load resistor wires from the lower control board. Be careful not to damage the connector on the lower control board or the load resistor wires.
Set your volt meter to the setting larger than and closest to 2.5 ohms. Insert each lead from your volt meter into the pins of in the wire connector of the load resistor.
Look for a reading of 2.5 ohms (+/- 10%). If your reading is outside the range, the load resistor should be replaced.
This video covers general resistance troubleshooting for the Stairmaster 4400CL, 4600CL, and SC916 Steppers.
Tools Needed: Multi Meter, Jumper Wire
Resistance problems could be either mechanical or electrical in nature.
Mechanical problems are easily identified by noise. If a grinding noise is heard while pedaling, this is an indicator the drive hub assembly is having a problem. If a ratcheting sound is heard while pedaling, this is an indicator of a loose belt or a belt that could be coming off.
Once you've eliminated the possible mechanical causes for resistance problems, then it is time to investigate the electrical system.
The easiest test of the electrical system when investigating a resistance problem is to step onto the pedals and access Diagnostics. This is done by pressing Level ^, 6, ENTER. (DIAGNOSTICS will appear in the upper display window.) Press Level Down twice to get to the alternator test. (ALT TEST will appear in the upper display window.) Press ENTER to begin the test. As the video shows, resistance drops out when the test begins. So, if this occurs, press the Level ^ one time. This will turn the field ON. This verifies that voltage is passing from the display through the display cable to the lower control board. This confirms there is good communication between the console and the lower control board and that the voltage is being supplied to the alternator. If resistance is lost during this portion of the test, inspecting the cable should be the first step of action. Look for bent pins, loose connection or crimped wire.
Other components of the electrical system to inspect for resistance problems are the battery, load resistor, speed sensor and alternator.
We'll discuss the battery first. In order to get a proper reading, testing the battery should be done with the pedals in motion. There are 3 different battery readings a person may encounter. A reading of 6 VDC or greater indicates a good battery. A reading below 6 VDC but higher than 4.8 VDC indicates the battery needs charged for 24 hours. A reading below 4.8 VDC indicates your battery is bad and needs replaced. For more information, watch our battery testing video.
If your battery is good, the next item to check is the speed sensor. The speed sensor should be spaced a business card thickness away from the speed disc. If the speed sensor is spaced properly, the function of the speed sensor can be verified by confirming that proper voltage is present. For more speed sensor troubleshooting, watch our video on speed sensor testing and adjustment.
Next to inspect is the load resistor. Load resistor testing is pretty simple. Load resistors are ohm rated, and you want to verify the proper ohms for the load resistor being tested. Load resistors can cause the resistance to come and go. This means you may pedal a few steps and then the pedals will drop or loose resistance. Then, as the load resistor cools down a bit, you may get resistance again for a few steps. If the resistance goes back and forth like this, the load resistor likely needs replaced. For more information, see our load resistor testing video.
The last electrical component to inspect when investigating a resistance problem is the alternator. The alternator can be easily tested by performing the B+ to Field jumper test. For details on how to perform this test, watch our alternator testing video.
Speed Sensor Testing and Adjustment for Stairmaster 4400cl and 4600cl Steppers
Testing and Adjustment of Stairmaster 4600CL and 4400CL Speed SensorTools Needed: Volt Meter, 7/16" Wrench
A common misconception about battery powered units, it that it only requires you to step on the pedals to power the console; when in fact the speed sensor plays a major role in powering the console.
If you step on the pedals and they fall to the floor due to the console not powering up so there is no resistance, you should check the speed sensor.
The speed sensor is mounted to the alternator and reads the speed sensor disc when the unit is pedaled producing an AC voltage. The voltage from the speed sensor can be tested at the connection of the speed sensor to the lower control board. The connection is a red and black wire. Using AC setting on your volt meter at its lowest range, place the red lead to the red wire and the black lead to the black wire. Make sure the leads of the volt meter are making a good connection. Now step on the unit and verify the voltage from the speed sensor. A good speed sensor will produce about 3 VAC before the console powers up.
If the voltage is not correct, inspect the adjustment of the speed sensor. It may be necessary to adjust the sensor closer to the speed sensor disc. Proper gap of the speed sensor to the disc is about the thickness of a business card.
Retest unit after making speed sensor adjustment.