Setting the speed control adjustments correctly is critical for proper speed control operation. Read through your instruction manual and carefully follow the setup procedures. Be sure to adjust your transmitter to the recommended settings before you begin. The basic procedure is to: (1) Adjust the neutral, then (2) Adjust the high speed with the ESC adjustments, and (3) Adjust the brake or reverse with the transmitter adjustments. If you encounter problems with this setup procedure, review the following to determine the problem with your system:

• Set-up LED stays solid red and adjustment pots have no effect. No signal from the receiver to the ESC. Check the wiring sequence of the receiver harness. Check for damaged wires in the receiver harness. Try swapping the ESC plug with the servo plug to check for a problem with the throttle channel on the receiver.

• Neutral adjusts okay but transmitter throttle has no effect (LED stays red). ESC is plugged into incorrect receiver slot. ESC should plug into channel 2 of receiver. Try swapping the ESC and servo plugs in the receiver. Test the throttle channel with a servo for proper operation.

• Neutral adjusts okay but unable to get the solid green at full throttle. ESC not getting enough "electronic throw". Adjust transmitter throttle throw rates and endpoints to their maximum positions. Rotate the high speed pot fully clockwise.

• Unable to get blinking green at full brake (or solid green at full reverse). ESC not getting enough "electronic throw" for set-up procedure. Adjust transmitter throttle throw rates and endpoints to their maximum positions. Adjust transmitter mechanical settings to allow maximum trigger push travel. For forward only ESCs: Adjust the transmitter push brake adjustment so that the green LED just starts to blink. Adjusting past this point will make the brakes unpredictable. See Brakes Fade or Are Unpredictable section

More information on Pot Adjustments.

• Incorrect receiver placement. This is the most critical area for radio noise. Keep the receiver and the antenna away from all of the electronics. The battery, motor, speed control, and the motor and battery wires all radiate radio noise and can cause radio interference. Even a metal or graphite chassis can funnel radio noise from these components to the receiver. Try mounting the receiver on its edge. Try mounting the receiver on different edges by rotating the receiver. Certain components in the receiver can be polarized in relation to the interference, making one orientation better than the other.

• Bad electrical connections. Check the electrical connections on the battery pack, battery wires, motor wires, and receiver plugs. Check plugs for a tight fit and clean surfaces.

• Bad motor, servo, or battery pack. Sometimes the motor, servo, or the battery pack has a bad internal connection causing radio problems. Try replacing the motor, servo, and the battery pack. It is best to replace one component at a time.

• Incorrect wire routing. If the positive and negative power wires are separated from each other, they will radiate noise between them. For the least amount of noise, keep power wire pairs twisted together. Add two or three twists to the red and black wires that go to the battery. Do the same to the red and blue wires that go to the motor. Keep the wires as short as possible and keep them away from metal or graphite chassis.

• Damaged or missing motor capacitors. The motor capacitors supplied with the ESC are used to reduce the amount of radio interference generated by the motor. Replace if cracked, broken, or missing. Refer to How To Install Motor Capacitors for more information.

• Damaged or missing Schottky diode. An external Schottky diode soldered at the motor will reduce radio noise by shunting the voltage and current spikes at the motor. Even if you have a speed control with a built-in Schottky diode, such as the 410-M5, the current spikes must travel from the motor to the speed control which will increase radio noise. [Additional Schottky diodes are available in Novak kit #5640]. Refer to How To Install an External Schottky Diode for more information. NOTE: Never use Schottky diodes on reversible ESCs or damage will occur.

• Damaged or out of tune receiver. After extended use and crashes, the receiver can become damaged or out of tune. All receivers have sensitive tuning coils that can move as a result of a hard impact.

• Damaged or incorrect crystals. Crystals can be damaged from hard impacts and the radio system will lose range or stop working. Also, always use matched crystal pairs supplied by the transmitter manufacturer. Different manufacturers use different crystal specifications that affect how the signal is processed. A mismatched pair might work in a radio system, but it will not have the range of the correct crystal set. Be sure the transmitter crystal is in the transmitter and the receiver crystal is in the receiver.

• Transmitter out of adjustment. It is best to use frequencies on or near the frequency that the transmitter came on. Jumping from one end of the band to the other will decrease your range. As you get more involved in R/C, you might consider upgrading your radio system. FM radio systems tend to have more range and are less susceptible to radio interference. Radios on 27 MHz may also give slightly better performance. You might even consider a PCM style radio for increased range and noise immunity.

When your speed control overheats, the throttle will shut down. If the temperature increases too rapidly, the speed control can be damaged. Overheating is caused by too much current through the speed control for the amount of cooling that it receives. The following are causes for overheating and thermal shut-down:

• Motor over-geared. An over-geared motor will draw excessive current causing the ESC to overheat. Try a smaller pinion gear on the motor, or a larger gear on the axle or gear box.

• Shorted motor or binding transmission. A shorted motor or bound transmission causes excessive current. Remove motor and verify transmission spins freely. Try replacing motor.

• Insufficient cooling to the speed control. ALWAYS use the supplied heat sinks. Adjust the heat sink fins for a snug fit over each of the transistors. Try placing the ESC so that air can flow through the heat sinks. Cut vents in the body to direct air over the speed control. Use the optional ESC cooling fan (#5645) to cool the heat sinks. Replacement heat sinks sets are available for purchase.

• Radio interference. Radio glitching can cause the ESC to rapidly switch between forward and brake. This stuttering can quickly overheat both the drive and brake transistors.

• Reversible ESCs. If the throttle reversing switch on the transmitter is in the wrong position, the forward transistors will be used for reverse drive and reverse transistors for forward drive. This will quickly overheat the reverse transistors since they have less power handling capability. With the reverse delay set to maximum, there should be a delay (a braking period) from forward movement to reverse movement if the transmitter reversing switch is set correctly.

• ESC brakes are not set up properly. The brake adjustment is very sensitive on the speed controls. If the adjustment is allowed to go past the blinking green light, the brakes will become unpredictable. To set the brakes: (1) Adjust the brake travel limit on the transmitter to minimum with either a mechanical stop or an electronic limit adjustment: (2) While holding full brakes on the transmitter, slowly increase the limit adjustment until the green light just starts to blink: (3) Reduce the limit so that the LED blinks about once per second. It is critical that you remain on the "neutral side" of the blinking LED. Note: If you have problems with this step, please call our customer service department. We have specific adjustment procedures for some of the more popular transmitters.

• Brake transistors are overheating. If the brake transistors overheat, the voltage drop increases and the brakes will lose power. Try replacing the external Schottky diode (if applicable). If the diode is missing or damaged, the brakes will overheat and fade. Even using an external Schottky diode on ESCs with built-in diodes will greatly reduce brake heating. [Additional Schottky diodes are available in Novak kit #5640]. Refer to How To Install an External Schottky Diode for more information.

• Motor magnets are weak or motor is over-geared. Try replacing the motor or using a smaller pinion gear on the motor or a larger spur gear on the axle or gear box.

• Transmitter throttle reversing switch set incorrectly. With the reverse delay set to maximum, there should be a delay (a braking period) from forward movement to reverse movement if the transmitter reversing switch is set correctly.

• Motor wires are backwards. If the transmitter throttle reversing switch is set properly, the motor wires are reversed.

• Switch turned off with motor running. If you turn the switch off while the motor is running, the motor can generate enough voltage to keep the electronics active and the motor can continue to run. If the motor is allowed to run, it can damage the speed control. Always turn the switch off after the motor has stopped turning.

• Switch turned off with motor stopped. If you turn the switch off with the motor stopped, then the motor starts afterwards, there is something wrong with the speed control. If you drive near water or mud, carefully remove the case and check for moisture. Dry speed control with compressed air or a hair dryer if necessary.

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