How do I interpret the C220 Status LEDs

The C220/C920 controller contains a single red/green/blue LED which indicates the operational status of the controller using various colours and blink rates.

Lamp State	Interpretation
Steady Frosty White	The controller is operating properly and waiting for a radio link from a portable remote controller.
Steady Green	The controller has a radio link from a portable remote controller.
Steady Turquoise	Some applications feature a colour change of the status lamp from Steady Green to Steady Turquoise to indicate that the controller has a radio link from a portable remote controller and is being commanded to turn on an output aside from LOOP OUT.
Steady Deep Blue	The controller has been placed into Matching Mode, and is waiting for another device to match with it. Normal operation will resume after a device has attempted to match with the controller, or after one minute if no device attempts to match.
Quickly Blinking Green	1. An activated output is overloaded (the connected load is drawing too much current) or the output is short-circuited to ground; or 2. The current-controlled output I/O 16 has detected a solenoid with unusual inductance or resistance. This is a warning indication and the controller will continue to operate, with the possible exception of an output that has excessive load or is shorted to ground.
Quickly Blinking Blue	A recently activated output was overloaded for long enough to trigger the over-temperature protection of the associated output driver. The controller will continue to operate, and the affected output will resume operation when the driver cools down sufficiently.
Slowly Blinking Turquoise	The controller has detected that its supply voltage is below 8.0 volts. The controller will attempt to continue operating, but some outputs may not be available or the controller may restart itself if the voltage drops further (e.g. due to turning on an output function connected to a load). Check the wiring and/or the machine's battery and charging system.
Quickly Blinking Turquoise	The controller has detected that its supply voltage exceeds 34.0 volts. The controller has turned off its output functions and will resume operation when the supply voltage decreases to an acceptable level.
Alternating Blue and Red	1. The controller has detected power being fed back into one of its outputs, and it is not a normal condition for that output to be powered externally in the machine involved; or 2. The controller has detected that an internal power driver has failed in the active state. If the condition was transient,power-cycling the controller will restore it to operation.
Alternating Green and Red	1. The LOOP OUT signal has been short-circuited to ground; or 2. The controller has detected an internal fault in its safety loop (E-Stop) system . If the condition is transient,power-cycling the controller will return it to normal operation.
Quickly Blinking Violet	The controller has detected an internal error condition that prevents it from operating. This condition may occur temporarily after reprogramming the controller's firmware via the USB programming cable, in which case power-cycling the controller will return it to normal operation. The details for this condition are that the ELR board is receiving messages from the radio module, but (at least upon start-up) the radio module is not receiving (or did not receive) messages from the ELR board. This has been seen in production in C220s with ELR-CAN boards, by tilting the board in the mating Cinch connector. It's possible that the radio module powers up but the ELR board is not fully running.
Quickly Blinking Orange	1. The controller is unable to communicate with its base (ELR) board; or 2. The controller has detected an error with the PWM driver chips. This condition may occur while updating the firmware of the base (ELR) board using the USB programming cable, in which case there is no reason for concern. This condition will clear by itself once the communications and/or PWM driver has returned to normal.
Steady Violet	1. The controller's radio module is not programmed; or 2. The controller's radio module has failed. Programming or replacing the radio module is required for the controller to operate.
Steady Orange	1. The controller has not been assigned a radio key; or 2. The controller has been programmed with an incorrect firmware image; or 3. The controller is in USB programming mode, meaning that a positive voltage was present on its ‚ÄúUSB VBUS / CAN0 L‚Äù signal (pin H3) during power-up (e.g. the controller is connected to a special C220 programming cable with the USB connector plugged into a computer). Configuration or reprogramming is required for the controller to operate.
Very Slowly Blinking Red	The base (ELR) board is very old (revision 1, or revision 2 with D37 and D38 installed) and cannot be operated with any of the modern firmware being delivered to customers today or in the future. Replace the board.
Steady Red	1. The controller is not being fed power and ground properly. The power and/or ground wire(s) is loose or disconnected, or the 30-way connector is not completely mated--check the 1/4"" hexagonal-head securing screw; or 2. The base ELR board's processor is not programmed. The wiring or programming problem must be remedied in order for the controller to operate.

Note that it certain lighting conditions and with certain viewing angles, it can be difficult to determine the exact colours being displayed. There are also times when an LED pattern can map to multiple conditions. Using Diagnostic Mode can be helpful in these situations.