COP (toyotas) and MS standalone tach issue
#61
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Its that the tach outputs from the COPs need that 1v signal that would normally come from the ECU.
So as talked about,
Standalone MS = 1k from 12v to tach wires (which as Lazzer mentioned, can be done at the ecu plugs easily... so you can still merge the 2 wires together for possibly other configurations)
MS with OEM Ecu = just jumper the 2 wires together.
OEM Ecu = just jumper the 2 wires together.
#64
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"High voltage" being 12v thru the resistor instead of a regulated 1v? I don't think the voltage really needs to be regulated. It's just something the tach needs to compair a 0v tach pulse against. I'm suprised Mazda didn't do all this in the tach itself. It seems overly complicated just for a tach signal. 1k limits the current at 12ma (.012a). Not enough to fry anything. If you -really- want to lower it use a resistor divider (series network) of 1k to v+ and 10k to ground. The center will give you 1.1v.
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