NSX Plug-in tacho issue

[yorl]

Ok, we did an NSX with the plug'n'play adapter harness. The car runs fine, makes power and all that, but I can't get the tacho output to work. I've had it in storage since last summer and the customer is picking it up in a month, so I'd like to get rid of that bug. Any ideas?

[stevieturbo]

Can you put the original ecu back in to determine the type of signal it sends to the tacho itself ?

Can you make the tacho do anything when you test the output you have used on the ecu ?

[TimH]

Many loom adapters provide a pullup resistor (varies between 100R and 1k) because the Syvecs output used for the tacho doesn't actually switch between 0 and 12V (it's more like a relay contact).

I would probably try a 1k resistor between the S6 tacho output pin 4 and a source of 12V (which you can find on pins 12, 19, 20 and 21).

[yorl]

Stevie, the car is turbocharged now with biiig injectors, I don't think it would run for long with the stock computer... plus I also changed some sensors.
Tim, I'll give it a try and let you know asap. Thanks!

[yorl]

Forgot to update. The 1k resistor and 12v worked great. Thanks!