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V1.0
RUNGU Electric Juggernaut Mid-Drive Version (MDV) User Manual
–
2018 model year
Copyright 2018 Standard Bearer Machines, LLC
46
3.
Check that the Battery voltage is greater than 52V. IF the battery is discharged, you
’ll have less
performance than when its charged.
Problem: The display shows Error 21
–
Speed Sensor not functioning, but the MDV continues to work.
The speed sensor has become unattached from the motor controller or the detector magnet has fallen
off or fallen out of alignment with the sensor. This can happen after changing a rear tire or performing
other service on the rear wheel.
Solution:
1.
Check that the speed sensor is in place and connected. When you turn on the MDV, a red light
on the end of the sensor should light. If not,
2.
Check the placement of the magnet relative to the speed sensor. The circular sections should
line up and there should be a maximum distance of 1/8”
(3mm) between the two as pictured
below. To test it, realign the sensor and magnet, lift the rear wheel and turn on the throttle.
The red light in the back of the sensor should flash every time the sensor detects the magnet.
Repeat the adjustments. Thi
s may take several iterations to correct. If it doesn’ work,
3.
Contact Rungu Support to investigate other measures.
Problem: I am not getting the advertised range
On flat ground, you’ve tested the MDV as described above and you fail to get the stated ra
nge.
Solution:
1.
Check the tire pressure. The stated range uses tires at their highest pressure on pavement.
2.
Verify the load carried by the MDV is around 176 lbs (80kg).
3.
Check the battery voltages
–
The battery should be 56-58 V with a full charge and be fully
discharged at 42V. If your battery is not operating in this range, contact Rungu for detailed
trouble shooting.