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scarceller scarceller is offline
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Join Date: Oct 2006
Location: Southern MA
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Originally Posted by cgarr View Post
Don't you ever sleep! I'm still trying to find a good rpm signal to tap for my LM-1?
The coil '-' signal should work perfectly for RPM. I use this in my TechEdge install. Many folks try to use the coil '+' side but that won't work. Have you tried the coil '-' signal? You can get this at the DME Harness from pin #1 you may also need to put a diode in series into the line. Put the striped side of the diode toward pin DME #1 then wire the other side to the LM-1. The diode prevents negative going spikes (less than ground) from being seen by the LM-1. These spikes often occur in hi-voltage ignition coils and could confuse the LM-1. The diode may or may not be needed but it's a good idea to put one in. Get a 1N4001 diode from RadioShack for this.

Good luck
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Old 09-30-2008, 09:09 AM
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