: 4 Digital inputs, 1 MOSFET output (1.0 AMP), and 5 push-buttons. Key Menu Functions
Without the manual, those blinks are just a frustrating light show. With the manual, you have a diagnostic key. curtis 3501 manual
Finding an official PDF is harder than it should be because Curtis Instruments tightly controls distribution to OEMs. Here is the realistic roadmap for a technician: : 4 Digital inputs, 1 MOSFET output (1