3 Amigos can come on for 3 reasons (and I have experienced all 3).

1) Bad ABS modulator - sometimes the ABS modulator's shuttle valve. If the error points to the modulator and you dont have an extended warranty, try the shuttle valve first. The repair is significantly cheaper. A few hundred versus $2-3,000 for the modulator.
2) Right front wheel hub going bad.
3) After market break pads. some of the after market pads can cause a high pitched vibration which sets off the ABS sensors. Solution is replacing the brake pads with genuine LR pads.

In order to diagnose, you need Rovacom, T4 or Autologic computer. If the lights are coming on, the ABS system is not functioning properly and i would not trust it. It needs to be fixed - just my opinion.