Free warning buzzer/alarm
Free warning buzzer/alarm
Sending positive voltage to pin 9 of the stock seatbelt warning buzzer will activate it as long as the voltage is applied. Sending power to the blue wire of the seatbelt switch harness will do the same.
It would work well for manual glowplugs, high water temperature, low oil pressure, overboost, etc.
It wouldn't difficult to make. All it consists of is a relay that breaks power to its own coil when energized and a few transistors and resistors to control the 4-8 seconds timing of the seatbelt buzzer/light.