my thermostat housing has 2 ports for sender.. the boat came with 2 of the same sendeers in it. the parts book shows 2 different senders/sensor?
are they supposed to be different? 1 temp sender for gauge and 1 sensor for alarm system?
Are you sure both sensors are the same? Temp gauge uses a sensor that varies the signal directly with temperature change. Alarm system usually uses a sensor that is either an off or on switch depending upon temperature.
