help please, tach not working , yellow/red wire with no signal

[mallbor240SR]

hope someone can help me , here is my problemi just finished my sr20det swap on my '90 hatchback, got a jdm cluster but the tach doesnt work, as the FSM says, i checked the signal coming from the yellow/ red wire coming from the ecu using a voltimeter but i didnt get any signal, later on i found a one wire plug near to the battery with a yellow/ red wire but isnt plugged to anything, i checked continuity betwing that plug and the wire on the ecu side and there is continuity so im wondering if maybe that plug has anything to do with the rpm signal .thank you for your help

[RMiller]

Did the original tach work with the KA? Did you connect all the plugs on the SR transmission? Should be plug and play; I have a jdm cluster.

[tazjig]

if anyone else has any other ideas, i would also like to know, i have the same problem.

[mallbor240SR]

yes the original tach worked with the KA .can anyone tell me how many plugs are supposed to be connected to the transmission?thanks

[SpeedRacer1]

I have two plugs unplugged and one plug connected on the transmission. I believe its the speed sensor.

I dont know for sure but I believe the tach gets its signal from a part of the ignition system like the one of the coils (or something else).

[RMiller]

Oh yeah, my bad. And I did that wiring, I'm an idiot.

The yellow/red stripe wire by the ECU is the tach signal. You just need to cut off the plug from you KA harness and your SR harness, leaving a little bit of wire left, and match up the two yellow/red stripe wires.

You didn't splice a wire from the ecu to the main harness did you? The wire to splice is in that small group that goes to the little plug that's a few inches from the ecu. The wire you're looking for comes from a pin on the ecu, so no wire in the engine bay will do you any good.

If it still doesn't work, the yellow/red stripe wire may not be secured into the ecu pin. You can Google the pin layout and find which pin the tach sensor is. Then just connect it all up. If it doesn't work at that point, then I don't know what to say.

[mallbor240SR]

ok i found two yellow/red stripe wires by the ecu , the one i spliced comes from the main harness directly to the little white plug by the ecu , the other yellow/ red stripe wire comes from the main harness to big blue plug on the ECU, is this the one i need to cut and splice to the white harness then?

[SpeedRacer1]

They are actually the same wire. Thats the tach signal wire. The two wires are actually one wire that gets split off about 10 inches away from the ECU under all the electrical tape.

[RMiller]

Heh, it's been a while.

The yellow/red wire has to get cut off the little SR interior harness plug and attached to the yellow/red wire that's on the KA interior harness plug.

Sorry, I think I'm talking about stuff without remembering what it looks like. Have you done what I wrote above?

[mallbor240SR]

thas exactly what i did, but as i said before the yellow/red wire has no signal, and my tach doesnt work.does anyone know anything about the plug in the engine bay , by the battery with yellow/red stripe wire ?

[tazjig]

Just curious if you solved the problem

[RMiller]

So that wire goes to an unattached plug in the engine bay, that's probably your problem. Somebody needs to just look in their engine bay to help you out. My brother's been using my car so I haven't been able to check it out for you, but I will when I can, maybe tonight.

[mallbor240SR]

i havent solved the problem yet,i was checking the FSM and it looks like that plug by the battery with a yellow/red stripe wire is the check conector for the tachometer, thas how they call it in the FSM . anyways i dont know if thats supposed to be plugged to something, because it has a cap on it.my car wont start now, im getting no spark , fuel pump isnt working, red led on ecu wont turn on when ignition is ON ........looks like my ECU is gone ill try to fix this problem then ill go back to my tach and see if i can get it to workthanks for your help guys.

[SpeedRacer1]

Or maybe you need to screw your ECU in all the way.

[RMiller]

Have you ever gotten the engine running? Does it crank? Check your fuses. Do you have any power, like to the lights or anything? Recheck you wiring.

[mallbor240SR]

yes the engine run for about two weeks, it cranks but no spark and the fuses are ok, i did screwed the ecu all the way in and nothing

[SR20DETPoweredS14]

BTW where did you buy that JDM Cluster because im intrested in buying one myself.

[mallbor240SR]

got it on ebay a month ago.

[RMiller]

Sorry, I'm still not sure on something: Can you drive the car? Have you ever had spark? How do you know the tach doesn't work?

[mallbor240SR]

yeah i drove the car with the sr20 in it already, for two weeks with out tachometer until i got this no spark problem and now i cant find a ecu # 62 so i can see if tha's whats causing my spark problem .I posted this no spark problem at Nissan online mechanics.http://nicoclub.com/zerothread?id=92276

[nissanrcer240]

BTW where did you buy that JDM Cluster because im intrested in buying one myself.

I have one if your interested

[email protected]

Im having the same problem with my friends swap, except every once in a while the tach will start working for a few seconds and then cut back off. If you figure out what the problem was make sure to let us know

[5upra]

I have the same problem ...only I don't have a dohc cluster installed yet...just lazy...but I noticed it from my SAFCII. I has no tach signal coming in from the wire! Where exactly is the sensor for the RPM located? I will start at the source and work my way back!

[mallbor240SR]

i finally got my tach working, but not the one that is on the cluster, but an aftermarket one, using an msd tach adapter , works really good ill get the part number for you guys later.

[mackdaddy240]

I got a big aftermarket ricer tach And wired the signal wire directly to the yellow and red wire going into the ecu. Nothing, I'm trying to figure out where the ecu gets the signal from is it on the cam sensor? if it is I could just run directly to it like I did with the coil wire on the ka. Anybody know what wire on the cam sensor to splic into?

[mallbor240SR]

some told me to try that with the white wire on the CAS , and i tried but it didnt work.

the part number for the msd tach adapter im using is: 8913

[mackdaddy240]

Well I never got my HUGE FAZE indiglow gauge to work through the tach signal wire on the ecu, however I installed my JDM gauge cluster KMH And the tach works so now I have a faze gauge for sale, works great with a KA engine and I'm sure you can hook it up somehow on the sr so somebody buy it $100 obo