Treadmill overspeed. After a few minutes of normal operation the treadmill RPM goes UP to the max and later stops. I try to perform the calibration but after running at slow speed the treadmill stops and display reads FAIL. I changed the control board but Treadmill problem continue.

Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

True Treadmill Errors and Service Messages

• The True 600, 700, 725 and 750 series treadmills are equipped with built-in diagnostics and maintenance reminders that display either an error message or service message as they occur.
• The error messages that may be displayed by the built-in diagnostics are as follows:
  • E1:INCLINE
  • This means that the incline is moving when it has not been commanded to.
  • E1:MINIMUM
    • This is a minimum incline calibrating error that can be cleared by calibrating the incline.
  • E1:RANGE
    • This means the difference between the treadmills zero position and maximum incline is not sufficient.
  • E1:STALL
    • This means that the incline is not moving when it has been commanded to.
  • E2:OVERSPEED
    • This occurs when acceleration greater than 2.1 mph occurs as this is greater acceleration than anticipated.
  • E2:CAL
    • This means feedback cannot reduce or increase speed to target and error can be cleared by calibrating treadmill.
  • E3:EEPROM
    • This error happens when a data error is detected on the EEprom. The control panel needs replaced if this error occurs.
  • E5:SENSOR
    • This error occurs when there is no speed or RPM feedback detected from speed sensor.
• The service messages that may be displayed by the built-in maintenance reminders are as follows:
  • S1:LUBE
  • This service message displays when it is time for inspection of the deck lubrication system.
  • S2:CLEAN
    • This service message displays every 500 miles and is your prompt to clean the treadmill.
  • S3:MOTOR
    • This service message displays every 2500 hours and is your prompt to check the motor brushes.
• This information should help you understand the cause of the error message or code and how to take action to repair your True treadmill

Errors for True Treadmills E5 Sensor E2 Cal S1 Lube and more

Ok. So the first thing to try is to calibrate the speed.
You do this by doing the following:

• With the SAFETY KEY in place, hold the ELEVATION UP and SPEED DOWN buttons for five seconds. The console will beep twice, "ENG0" will appear in the Distance window, and a number will appear in the Elevation window.
• Press SELECT until "ENG3" appears; this is for Auto-Calibration.
• Press START to Auto-Calibrate.
• The treadmill will calibrate minimum and maximum speed, and minimum and maximum elevation. When Auto-Calibration is complete, the treadmill will reset to User's start screen. This process takes three to five minutes.

Make sure there are no errors. . .and that the speed goes from super slow to super fast and then stops. . .. if it stays slow. . or stays fast. .or error code appears during calibration, there is a problem.
If after a good calibration sequence, if it still does the stopping and E-1 after 10 seconds. ., then you need to (Power off and disconnect treadmill). . .then unplug the speed sensor from the lower power board, blow into the connector on the wire, and add a little contact cleaner spray to the connector on the board.
Recap: If it actually runs. . .but stops after a few seconds. . but the calibration runs and passes fine. .. .more than likely it is a speed sensor misread or a faulty speed sensor.

hi,
Try AUTO-CALIBRATION first. For that do the following.

With the safety key in place, turn the treadmill ON . Press and hold SELECT. Now you can perform auto-calibration by pressing START.

(The treadmill will run through minimum and maximum speed and elevation. This will take 3 to 5 minutes. Let the treadmill perform this complete function. "END" will appear when auto-calibration is complete. When auto-calibration is complete, it will take about 30 seconds for the treadmill to reboot and return to the start-up screen)

If it doesn't help then the motor control module is faulty. You have to replace or repair the motor control module.

OK

Press the Stop and the Speed Up keys down while inserting the safety key. This should get you into calibration mode. Press the Stop key one time. The Time window should read EP:2P. Some newer models may also say FP, Pass, or the like. This means that it passes the EPROM test. If you cannot get into calibration or if the EPROM test fails then the upper console will have to be replaced.
If you get pass to this point then proceed with the calibrating the incline and speed.
Press either incline key and the incline will calibrate automatically.
Be careful the treadmill will run at full speed in the next mode DO NOT STAND ON THE WALKING BELT.Press the Speed Up key and hold it down until 85 is shown in the Distance window (some models may show the 85 number in another window).
If the top speed of the treadmill does not match the displayed speed on the computer console, adjust the max speed potentiometer (pot) on the motor control board. This is the board that the red and black motor wires connect directly into in the motor area. The Max Speed pot is clearly labeled
The max speed potentiometer is a small square with a mobile center and is located in one corner of the board and is labeled MAX SPD. It is near the harness that carries the speed signal labeled H,W,L. Using a small insulated screwdriver adjust this potentiometer clockwise to speed up and counter-clockwise to slow down the max speed of the treadmill. A tiny turn of this potentiometer will make a big difference in speed so be careful when making adjustments.
It is not important to get the speed set exactly at the max speed of the treadmill but do make sure to get the speed within .2 MPH of the max speed of the treadmill. For instance if the max speed of the treadmill is 10 MPH, make sure to have the speed set between 9.8 MPH and 10.2 MPH. Some models have a 12 MPH top speed, so please check your manual if you aren’t sure.
After completing calibration of the speed, press the Speed Down key. The treadmill will automatically return to 0 MPH. Please allow the unit to stop completely before continuing. Press the Stop key once and remove the safety key.

Unplug unit remove motor shroud then start calibration procedure.
Press the Stop and the Speed Up keys down while inserting the safety key. If you cannot get into calibration then upper console needs to be replaced.
Press the Stop key one time. The Time window should read EP:2P. Some newer models may also say FP, Pass, or the like. This means that it passes the EPROM test. At this point if it show 2F FF or Fail then upper console needs to be replaced.
Press either incline key and the incline will calibrate automatically
BE CAREFUL, THE TREADMILL WILL RUN AT FULL SPEED IN THIS NEXT MODE! DO NOT STAND ON WALKING BELT.
Press the Speed Up key and hold it down until 85 is shown in the Distance window (some models may show the 85 number in another window).
If the top speed of the treadmill does not match the displayed speed on the computer console, adjust the max speed potentiometer (pot) on the motor control board. This is the board that the red and black motor wires connect directly into in the motor area. The Max Speed pot is clearly labeled.
The max speed potentiometer is a small square with a mobile center and is located in one corner of the board and is labeled MAX SPD. It is near the harness that carries the speed signal labeled H,W,L. Using a small insulated screwdriver adjust this potentiometer clockwise to speed up and counter-clockwise to slow down the max speed of the treadmill. A tiny turn of this potentiometer will make a big difference in speed so be careful when making adjustments.
It is not important to get the speed set exactly at the max speed of the treadmill but do make sure to get the speed within .2 MPH of the max speed of the treadmill. For instance if the max speed of the treadmill is 10 MPH, make sure to have the speed set between 9.8 MPH and 10.2 MPH. Some models have a 12 MPH top speed, so please check your manual if you aren’t sure.
After completing calibration of the speed, press the Speed Down key. The treadmill will automatically return to 0 MPH. Please allow the unit to stop completely before continuing.
Press the Stop key once and remove the safety key.

These units only have a calibration mode. The High end units generally will have that. If this is a Epic Then this calibration procedure should work.
Press the Stop and the Speed Up keys down while inserting the safety key. Press the Stop key one time. The Time window should read EP:2P. Some newer models may also say FP, Pass, or the like. This means that it passes the EPROM test. Press either incline key and the incline will calibrate automatically. BE CAREFUL, THE TREADMILL WILL RUN AT FULL SPEED IN THIS NEXT MODE! DO NOT STAND ON THE WALKING BELT. Press the Speed Up key and hold it down until 85 is shown in the Distance window (some models may show the 85 number in another window). If the top speed of the treadmill does not match the displayed speed on the computer console, adjust the max speed potentiometer (pot) on the motor control board. This is the board that the red and black motor wires connect directly into in the motor area. The Max Speed pot is clearly labeled. The max speed potentiometer is a small square with a movable center and is located near the three small speed wire connections labeled H, W, & L and is on the same edge of the board and the red and black motor wires are located. Using a small insulated screwdriver adjust this potentiometer clockwise to speed up and counter-clockwise to slow down the max speed of the treadmill. A tiny turn of this potentiometer will make a big difference in speed so be careful when making adjustments. It is not important to get the speed set exactly at the max speed of the treadmill but do make sure to get the speed within .2 MPH of the max speed of the treadmill. For instance if the max speed of the treadmill is 10 MPH, make sure to have the speed set between 9.8 MPH and 10.2 MPH. Some models have a 12 MPH top speed, so please check your manual if you aren’t sure. THIS IS A VERY IMPORTANT STEP BECAUSE YOU WILL GET AN ERROR MESSAGE IF THIS STEP IS SKIPPED. After completing calibration of the speed, press the Speed Down key. The treadmill will automatically return to 0 MPH. Please allow the unit to stop completely before continuing. Press the Stop key once and remove the safety key.

It sounds like the belt is bogging down, this condition is when the treadmill operates normally without a person on the belt and then slows down when someone steps on the belt or when the treadmill operates normally for a given period of time with someone on the belt then abruptly begins to slow down.
The only certain way to test for a worn walking belt is to take a DC amp draw . Trying to look at the belt or a feel test is highly unreliable. Better tests, if you lack a DC ammeter (they are expensive for a good one), are a coast test or an incline test.
The coast test is to get on the treadmill as the lowest incline setting and walk on the treadmill at 3 MPH. Pull the safety key and it should take you 2-3 full steps to stop fewer steps indicate high friction.
The incline test is to put the treadmill at max incline and walk on it at 3 MPH. If the treadmill operates normally at max incline but bogs down at minimum incline, replace the walking belt. Gravity takes over for the drive system eliminating much of the friction problem. On some heavily worn walking belts, this test will not eliminate the problem.

E4: Solution 1. Check power to the treadmill, as insufficient voltage to the treadmill can cause this error to reoccur. Check the power socket that the tread is plugged into. Eliminate any extension cords or surge protectors (plug the tread directly into a functional power source). Make sure the circuit is not overloaded. Make sure the circuit is NON-GFI. 2. Calibrate (See engineering mode for specific treadmill). 3. If calibrations do not hold, replace upper console. Note: Usually simultaneous with an E6. E6: Solution 1. Check the elevation plug connection at the lower board. 2. Check ALL large data cable connection at the lower and upper boards. 3. Calibrate (See engineering mode for specific treadmill) 4. Test/change large data cable (use large data cable information provided in the data cable portion of this Guide). 5. Replace elevation motor E7/E9: Solution 1. Certain lower boards have an LED that flashes when the magnet on the roller passes the sensor. Adjust sensor position if LED does not flash. See lower board basic troubleshooting for lower boards with the LED. 2. Unplug RPM sensor at the lower board. Check continuity. Treadmill will operate without sensor but cannot Autocalibrate. Calibrate manually. 3. Replace RPM sensor TREADMILL.TROUBLESHOOTING. AUTO CALIBRATION STEP 1 ENTER ENGINEERING MODE • With the SAFETY KEY in place, hold the “ELEVATION UP” and “SPEED DOWN” buttons for 5 seconds. “DGA3” will appear in the profile window and “EHG1” will appear in the function window. • You are now in ENGINEERING MODE STEP 2 ENTER AUTO CALIBRATIONS • Press the “ELEVATION UP” or “SPEED UP” to “EHG4”. • Press “SELECT”. STEP 3 • Press “START”. The treadmill will calibrate itself. This will take about 3 to 5 minutes. When AUTO is complete, “END” will appear in the window. Wait 10 to 15 seconds and the treadmill will reset itself to “P1”. STEP 4 • Press “START” to test the treadmill

Try Re-Calibrating 1st, here's how.
With the Treadmill off, press and HOLD the SPEED UP & STOP
keys, while holding the speed up & stop keys insert the Safety key (Magnet) release the speed up & stop keys. now press and release the stop key. now press the "incline up key" let the treadmill go to max incline,after it stops press and hold the "incline down key" let it go to minimum (completely lowered) you should now be re-calibrated.