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mr_240sx
12-17-2007, 02:35 PM
well im in the process of installing an HKS AFR and i need to hook up to a tach signal. anyways i got the ecu pin outs and fsm. anywho i go to find the wire and it turns out my tach signal wire coming out of the ecu is cut about 1 inch past my ecu plug. so wtf? the tach on the stock cluster works fine. so where the hell is it getting signal from? any imput guys? the instructions for the HKS AFR says it has to be a 5v signal so i take it getting the signal fromthe coil is out of the question right?

any info is greatly appreciated


im running zenki s14sr into an 89 coupe

http://www.200sx.org/s14-ecu.html
mr_240sx
12-18-2007, 07:09 PM
bump #1......

anyone have any imput?
NemeGuero
12-18-2007, 09:24 PM
splice the wire and hope it works. hahaha

seriously, maybe buy a Kragens tach and hook it up and see if it works. You could always return it. Or maybe you're looking at the wrong pinout?
PoorMans180SX
12-18-2007, 11:13 PM
Well since the ECU is telling each coil pack to fire, and it has a CAS to tell where the engine is at, then the tachometer wire must just be a secondary signal TO the ECU.

I would tap/splice your tach signal wire like it says and see where it goes.
mr_240sx
12-18-2007, 11:37 PM
ok ill try it in the AM and see where it leads me......
deesz
12-19-2007, 12:05 PM
grab it from the coil inside the engine compartment it is a green wire
or you can grab it behind your gauge cluster not sure of color just need to be an ac voltage...
PoorMans180SX
12-19-2007, 08:01 PM
how did it go?
mr_240sx
12-20-2007, 09:02 PM
got called into work....and have yet to have a chance to touch the car :(

looks like mybe tomorrow night or saturday morning...... if not then monday. i hate working to cover for my christmas spending.
NemeGuero
12-22-2007, 10:42 PM
lame.
GITRDONE
Jung918
12-23-2007, 12:36 AM
From what I understand, the signal comes from the sensor to the tach. Then the tach to the ecu. I am guessing the previous owner tried to remove the speed limiter.
mr_240sx
12-23-2007, 04:14 PM
alrighty well i finally got time to play around with the car again and it the tach signal from pin out #7 is coming from ecu and going out....so even though the wire was cut it works. wow i feel like a dumb ass as i should have tried that in hte first place but oh well.....all is good now! tks for the help guys!
NemeGuero
12-23-2007, 07:48 PM
Good job man.