CA Traveler wrote:
Could also be the controller or even wiring.
To check the panel: Look up the specs. Then locate the panel wires (not the controller output wires), disconnect one and then with good sun check the voltage which should be very close to Voc (open circuit). Next short the 2 wires and the amps should be close to Isc (short circuit). These 2 measurements are a very good test of a panels performance.
Ok, I don't wish to appear dumb but if he were to short the two wires from the panel, where would he place the meter leads. When shorted it would appear to be a close loop.