According to
this datasheet, it appears that the max amperage for the robot signal light port is 2.2 amps, with a typical amperage of 1.1 amps. The voltage is equal to Vin. Also stated is that there is a snubber diode put in parallel to protect it from any load inductance, so you might be able to use a light that has a slightly higher than recommended peak amperage, but that's really only if you don't mind the possibility of damaging the digital sidecar.