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gonzo24
04-06-2015, 01:06 PM
My tach reading drops to 0 under 1000 RPM. I have an EFII dual ignition system with the AFS dual RPM board. Ironically, my older ignition system was a dual LSE system with the same AFS board and the RPM was erratic above 2300. Any ideas?

Rob Hickman
04-06-2015, 01:30 PM
Did you have to change the pulses/2 rev with the new ignition?

gonzo24
04-20-2015, 09:59 AM
Did you have to change the pulses/2 rev with the new ignition?

Thanks Rob. No, it is set to 4 pulses per manual. I tried 2 pulses and the RPM then is displayed too fast as compared to actual prop as checked by optical tach. Can the RPM board be bad?

Shawn McGinnis
04-21-2015, 02:42 PM
Couple of things you can verify:
Ensure pin 31 WHT/ORN has +5v over pin 16 BLK.
Verify mag ground to firewall ground to ensure low Ω reading.
The 71420 should be wired into pin 32 of the engine sensor main cable.
You could also try a single mag connected straight to the EFIS.

Manual 3.02 Page 197