Originally posted by angryfist
quynce: what DEI alarm do you have? i have a viper 790 im trying to get working. it keeps reading "No or Low RPM". am i just not learning the tach correctly. i've tried both the C9 green of f the ecu and the uncommon injector wires too. according to my manual it says to hold the valet button and start the car, when the LED stops flashing and is constant then it is programmed. when i do this the LED seems to stop flashign instantly which does not seem right to me.
I used the Avital 3300. The tach learning should be the same, though, which is:
1) Start car with key
2) After car is running, within five seconds press and hold the valet switch
3) As soon as the LED comes on, let go of the switch. Do NOT keep it held until the light goes out, this usually creates problems.
If the LED doesn't come on, the wire you're using is no good. Good luck!