OK, scratch my "Harlan Window Switch Programming Tips" thread because either I don't know WTF I'm doing or the switch is bad. It seems to program fine; the # of cylinders and on and off RPMs flash back OK but when testing it the LED only comes on (and switched ground is provided) only after going past the off RPM. So if I have the switch set at 1500 for on and 2500 for off, the switch is only coming on @ 2500!!! It doesn't come on before the on or in between the on and off like it should, just after the off RPM. I'm using 4 cylinder mode.

WTF? I can't see any way I could have it wired wrong to make this happen. I have 12 ignition to the red, black to ground, RPM to green (via white #10 red PCM connector) and the white to 86 of my relay and 12V ignition onto 85 of the relay through the master arm and WOT switches.

So it goes 12V --> ARM toggle --> WOT switch --> relay 85, then relay 86 --> white Harlan wire.

Any help would be appreciated.

 

You can just PM him, He is always super busy but makes time to reply quickly! And if it where to be bad you need to talk to him anyways.

 

when I ordered my Harlan Window Switch last month, he provided "diode" to be spliced in between the coils on the relay. According to the additional instruction addedum the diode is needed due to "noisey" relays. E-mail Harlan about this diode. Hope it helps

 

I e-mailed him and he replied (within ~1/2 hour) that the LED on the unit is meant to light up only after the OFF RPM. I have an additional LED in the circuit but I think it's wired incorrectly. This may be a classic case of user error. I need to do more testing today.

 

Well Harlan's unit is functioning perfectly. I just assumed that the LED would light up during the ON period. It only lights up after the OFF RPM but the unit provides a ground during the ON window just like it should. I'm adding this lesson learned to my Harlan Window Switch Programming Tips thread.

https://ls1tech.com/forums/nitrous-oxide/155083-harlan-window-switch-programming-tips.html