Manually wiring speed sensor? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

.::SR20_240::. · 11-13-2005, 07:18 PM

okay well, ive been having this long going time with no damn speedo, i checked everything n i can't figure out why it isn't working. so i wanna wire it up my self straight from the speed sensor. how n what do i do to go about doing this? i have the 2 wires from the speedo coming up but where do i route them, what wires do i tap them into. any info on doing this would be greatly appreciated. i tried searching n ive been searching on this issue so please dont get mad at me for asking.

thx in advance!

Eternal_240Sx · 11-13-2005, 11:45 PM

I've had a few people ask me about this because their Kouki S14s w/ S13 SR20DET swaps run fine but they have no tach/speedo and don't want to jump into fixing the wiring (F3) of their swap a inexperienced shop did. Anywho this is how to ghetto rig your tach and speedo.

First pull your cluster out of the dash and you'll find three plugs in the back, two on either side and one in the middle. The plug in middle is going to be the new home of two more wires and the plug on the speedo side is going to get one more.

Tach
Run a wire up from the tach signal output on your S13 SR20 ECU (Pin #3 - yellow/red wire) to the gauge cluster. This wire is going to be spliced (solder them!) into the blue and black wire on the center plug on the back of the cluster. This is the tach signal input wire. Now the tach magically works.

Speedo
Slightly more complicated but simple none the less. The speedo uses a "two pulse" input (+/-) which basically means you're going to have to splice two wires into the guage cluster to get your speedo to move.

First get under your car and check out the speed sensor (If your not familiar it's bolted into the tranny near the back and has two wires coming off). The sensor has two wires coming off of it, one black (-) and one green I believe (+). It really doesn't matter if it isn't green because whichever one is not black is (+) . Splice a wire two each of these (make sure they are long enough to make it up to the gauge cluster) and run them both up over the tranny and through the hole for the shifter and then continue them up through the dash into the gauge cluster.

On the center plug (the one you wired the tach signal into) there is a red and yellow wire (speedo +pulse input). You need to splice the line you ran from the green (+) wire coming out of the speed sensor into.

The line you ran up from the black (-) wire from the speed sensor needs to be spliced into the black wire coming out of the plug on the speedo side of the console. This is the -pulse input for the speedo.

Now your speedo works. And a little tip. If your speedo is reading double (i.e. you are going 40mph and it says 80mph) you have an S13 speed sensor in your tranny and you need to replace it with an S14.

In conclusion: There is no reason to do this and is only for desperate situations. Wiring the tach/speedo through F3 is not that complicated and if you take some time to try you can do it.
by Yamaguchigumi

.::SR20_240::. · 11-14-2005, 11:07 AM

i dunno if this is the same for an s13 cluster but it didn't work, i tried it today, all it did was cause my tach to jump around while im driving. i spliced the green wire from speed sensor to the red/yellow wire in the middle, then the black wire from the speed sensor to the plug on the left side near the speedo/gas gauge to the black wire. didn't do anything =x jus caused some weird jumping out of my freakin tach. this is annoying me. i hate not knowing how fast im going.

Grandpa · 11-14-2005, 12:27 PM

S14 VSS wires are red and red/yellow.

.::SR20_240::. · 11-14-2005, 01:35 PM

what about s13... i have an s13.

11-13-2005, 07:18 PM	#1
.::SR20_240::. BANNED Join Date: Jun 2005 Location: south CA Age: 36 Posts: 324 Trader Rating: (0) Feedback Score: 0 reviews	Manually wiring speed sensor? okay well, ive been having this long going time with no damn speedo, i checked everything n i can't figure out why it isn't working. so i wanna wire it up my self straight from the speed sensor. how n what do i do to go about doing this? i have the 2 wires from the speedo coming up but where do i route them, what wires do i tap them into. any info on doing this would be greatly appreciated. i tried searching n ive been searching on this issue so please dont get mad at me for asking. thx in advance!

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11-13-2005, 11:45 PM	#2
Eternal_240Sx Zilvia Addict Join Date: Dec 2002 Location: norcal, bay area Age: 37 Posts: 674 Trader Rating: (1) Feedback Score: 1 reviews	I've had a few people ask me about this because their Kouki S14s w/ S13 SR20DET swaps run fine but they have no tach/speedo and don't want to jump into fixing the wiring (F3) of their swap a inexperienced shop did. Anywho this is how to ghetto rig your tach and speedo. First pull your cluster out of the dash and you'll find three plugs in the back, two on either side and one in the middle. The plug in middle is going to be the new home of two more wires and the plug on the speedo side is going to get one more. Tach Run a wire up from the tach signal output on your S13 SR20 ECU (Pin #3 - yellow/red wire) to the gauge cluster. This wire is going to be spliced (solder them!) into the blue and black wire on the center plug on the back of the cluster. This is the tach signal input wire. Now the tach magically works. Speedo Slightly more complicated but simple none the less. The speedo uses a "two pulse" input (+/-) which basically means you're going to have to splice two wires into the guage cluster to get your speedo to move. First get under your car and check out the speed sensor (If your not familiar it's bolted into the tranny near the back and has two wires coming off). The sensor has two wires coming off of it, one black (-) and one green I believe (+). It really doesn't matter if it isn't green because whichever one is not black is (+) . Splice a wire two each of these (make sure they are long enough to make it up to the gauge cluster) and run them both up over the tranny and through the hole for the shifter and then continue them up through the dash into the gauge cluster. On the center plug (the one you wired the tach signal into) there is a red and yellow wire (speedo +pulse input). You need to splice the line you ran from the green (+) wire coming out of the speed sensor into. The line you ran up from the black (-) wire from the speed sensor needs to be spliced into the black wire coming out of the plug on the speedo side of the console. This is the -pulse input for the speedo. Now your speedo works. And a little tip. If your speedo is reading double (i.e. you are going 40mph and it says 80mph) you have an S13 speed sensor in your tranny and you need to replace it with an S14. In conclusion: There is no reason to do this and is only for desperate situations. Wiring the tach/speedo through F3 is not that complicated and if you take some time to try you can do it. by Yamaguchigumi

11-14-2005, 11:07 AM	#3
.::SR20_240::. BANNED Join Date: Jun 2005 Location: south CA Age: 36 Posts: 324 Trader Rating: (0) Feedback Score: 0 reviews	i dunno if this is the same for an s13 cluster but it didn't work, i tried it today, all it did was cause my tach to jump around while im driving. i spliced the green wire from speed sensor to the red/yellow wire in the middle, then the black wire from the speed sensor to the plug on the left side near the speedo/gas gauge to the black wire. didn't do anything =x jus caused some weird jumping out of my freakin tach. this is annoying me. i hate not knowing how fast im going.

11-14-2005, 12:27 PM	#4
Grandpa Zilvia Member Join Date: Nov 2002 Location: Atlanta, Ga Posts: 182 Trader Rating: (0) Feedback Score: 0 reviews	S14 VSS wires are red and red/yellow.

11-14-2005, 01:35 PM	#5
.::SR20_240::. BANNED Join Date: Jun 2005 Location: south CA Age: 36 Posts: 324 Trader Rating: (0) Feedback Score: 0 reviews	what about s13... i have an s13.