There are a small number of potential sources of error that may be causing your controller to fail. These are listed below in the recommended order of operations to restoring function to your system.
Multimetre Testing - Control Box
As per the how-to guides, testing with a multimetre is the most effective method of identifying any issues with your control box.
Refer to Attaching the Power Jumpers to test resistance within the circuit. If the system fails any of the resistance tests, follow the steps within the guide linked.
If issues persist beyond the resistance testing, refer to Connecting Power to the Controller to test voltage.
Multimetre Testing - Power Supply
If insufficient or no voltage is detected, ensure your power lead has been properly connected to the control box,
If these checks do not solve the issue, the source of error is most likely located outside of, or separate to the control box.
Place the positive and negative prongs of the multimetre over your power source to check the correct voltage is being applied to the power lead.
If the voltage measured is insufficient or 0 Volts, we recommend checking it is first turned on, or if it is, changing to an alternate power source, such as another battery or power supply.
If issues persist, check that the in-line fuse is both inserted and in functioning condition. The solder joint in the red power lead should also be checked, and isolated from other components by using heat shrink.
Not All / Wrong Motor(s) Spinning
The source of error that causes the wrong motors to activate or ‘Spin’ is an incorrect wiring of the tether power wires within the control box.
For example, the left and right motors might be activated by the opposite switches, as a result of the wires being crossed.
First separate the clear case from the controller, and using the Tether Wiring Scheme how-to guide, ensure your controller has been wired correctly.
If this check / fixes do not solve the issues, the source of error may be as a result of incorrect wiring where the tether cable and motor wires connect.
Remove any heat shrink from around the solder joints where the tether and motor wires connect. First, check all joints are properly soldered, fixing any and checking for function before proceeding.
Next, de-solder the necessary wires, leaving any functioning motor-tether combinations untouched.
Using a small torch, such as that on a smartphone, check the de-soldered wires feed back to the correct motors within the frame of the ROV.
Note: The motor wires of the central vertical motor are usually shorter as they travel further within the frame - making them easy to identify.
Mark the motor wires with a ‘Top’, ‘Left’ and ‘Right’ indicator (in accordance with their motor position) to avoid future confusion, and first slip over a length of heat-re-solder them to the correctly coloured tether wire(s).
Once fully reconnected, check for full motor functionality, and finally cover the solder-joints with the heat shrink.