The BCDC Alpha chargers (25A, 50A, and 50R) enter standby mode with no LEDs when the vehicle is off and solar input is insufficient. Charging resumes only when the vehicle is running with adequate input.
A lack of solar charging can be caused by undersized cables, poor or loose connections, faulty fuses, damaged panels, or low light conditions. The solar input range is 9–48V, and issues like low voltage or poor grounding may not trigger a fault code.
Troubleshooting involves checking solar exposure, tightening connections, verifying grounding, and testing panel performance.
REDARC recommends seeking the support of a qualified auto electrician or technician.
Important
In this article we explain the need for testing to determine the cause of the issue. Testing may involve changes to the installation or wiring. For your safety and accuracy, REDARC recommends engaging a REDNetwork member or a suitably qualified auto electrician - Find Your Local Installer
This information is applicable to the following products:
- BCDC Alpha 25A DC Battery Charger (BCDC12025B)
- BCDC Alpha 50A DC Battery Charger (BCDC12050B)
- BCDC Alpha50 R DC Battery Charger (BCDC12050R)
What does this look like?
If the vehicle is not running and the system isn’t charging from solar, there will be no LEDs on the BCDC indicating that the unit is in standby.
If the BCDC displays no illuminated LEDs, the vehicle is not running but solar is connected this indicates the BCDC is still in stand-by.
Will the BCDC still charge my battery in this condition?
Providing the vehicle input to the BCDC is adequate, it will charge when connected to a running vehicle. While there is an issue with the solar input, the BCDC will cease charging once the vehicle has turned off.
What can cause this fault?
hen the solar input wire (yellow) is compromised from any of the following:
- Undersized cable
- Poor connections such as loose or damaged terminal/connections
- Faulty fuse protection
- Solar panel has a damaged cell or is faulty
- Solar panel is in low light/poor conditions – for example, poor angle to the sun or overcast weather
What is the solar input voltage range?
The solar input range for the BCDC Alpha range is 9-48V.
Why doesn't it display a fault code?
There could be an issue with the power supply such as:
- Input voltage is present and is below the turn on threshold.
- Poor ground (earth) but not severe enough to trigger a fault code.
How to determine the cause of this fault?
Below is a list of the common causes and repairs.
A) SOLAR PANEL IN LOW LIGHT
No action required, the BCDC will start charging when the solar panel is exposed to increased light, which could include an improved angle to the sun or better sun exposure.
B) LOOSE CONNECTION FROM SOLAR
- Ensure connection points are clean and not damaged or loose.
- Remove solar connector and ensure a good terminal contact is present (a tight connection).
- Ensure each crimp connection is strong, a small tug on each wire can confirm this.
- Inspect the ground (earth) wire to ensure it has a suitable ground connection, such as a terminal attached to a bare, unpainted metal surface.
-
Check if the solar panel is performing correctly. Refer to our solar testing procedure.
C) POOR SOLAR GROUNDING
In some applications, the auxiliary battery may not have been wired to the ground from the auxiliary battery negative terminal to the chassis and/or body.
Things to check:
- Using a multimeter, measure the voltage between the solar panel negative wire and auxiliary battery negative terminal. If greater than 0.5V is measured, excessive voltage drop is present.
- As a quick test, using a jumper lead, connect the auxiliary battery negative terminal to the solar negative wire and recheck operation.
- If the test was successful, either rewire the solar negative cable to the auxiliary battery negative terminal or run another wire from the auxiliary battery terminal to the solar grounding point.
- Re-check operation.
Note: Applications using a Smart Battery Monitor (BSEN500) or battery monitoring system that incorporate a shunt, the ground side of the sensor/shunt is the common ground point for all loads including the BCDC Alpha and solar panels.
The below image shows a typical BCDC install. This diagram shows the typical connection points with Solar input references.
