amimaxima

96 ek hatch obd2a

96 b18c1
96 gsr tranny

99-00 si engine harness obd2b

99-00 si speed sensor

the speedo isnt working and I cant figure out why.
it doesnt work with the 99-00 si computer or a p28

the tach wasnt working either but I ran a wire from the blue wire on the dizzy to the blue wire on the drivers side shock tower and that works now.

iamthefollower

could possibly be the wiring harness.

96_cvc_b16

sounds like a bad vss

amimaxima

the gsr tranny had a metal vss and 99-00 si harness the plug for the vss wouldnt plug into the gsr vss so i got a plastic vss from a 99-00 si put that in the gsr tranny and the harness plugs into to that vss

geneeunit

did you change the underdash harness to the 99-00 si's? and if you didnt, where did your third ecu plug come from? because the 96-98(OBD2a) and 99-00(OBD2b) harness's are different.. so you cant mix and match them.

hmoobhero

so is it working now? i had this problem before. turned out to be a blown altenator fuse located under the steering column. its fuse 15(7.5w).

amimaxima

the car is a 96 obd2a

the engine harness is 99-00 si obd2b

and the ecu is 99-00 si obd2b

the harness that plugs into the engine and ecu had 3 plugs 2 that plug into the ecu and one green plug that plugs into the under dash harness

i got the tach to work but i cant figure out whats going on with the speedo

hmoobhero

did you check the fuse? get another vss that you know it works and try it.

96 EX

I would check this fuse, my speedo quit working not too long ago and it turned out to be the harness underneath the intake manifold was shorting out. Here is the post I made about it and RonJ helped me through it.

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/speedo-quit-while-driving-2545274/
Read his post on the 1st page and go to the TSB link.

amimaxima

the vss was working in the car that it came out of

94EG8

Yep, I can pretty much guarantee you thats the problem. I don't know how many times i've seen this question asked. If you plan on running a '99 - '00 Si engine harness in a '96 - '98 Civic you must also use a '99 - '00 dash harness or you wont have a tach.

amimaxima

the tach works

geneeunit

i understand you got the tach working.. but its most likely not working HOW IT SHOULD BE.

the 99-00(OBD2b) underdash harness is REQUIRED if you are trying to use a 99-00 engine harness. the green plug which connects to the underdash has the 3rd plug for the ECU on it.
i KNOW, ive done it.
thank you.

amimaxima

alright so in order to get the tach and speedo working properly I have to get a 99-00 si under dash harness?

how hard is this harness to change? do I have to pull the dash out?

fireblaze2k1

No you can leave it in and change everything. Of course you have to take it out, "under dash harness". It's under the dash.

amimaxima

do you have to take the dash out

geneeunit

yes, you have to pull the dash, its really easy.

amimaxima

is swapping the under dash harness a for sure fix for the tach and the speed? also this under dash harness where does it plug into?

iamthefollower

why don't you just get the correct engine harness for you car instead of changing out these other harnesses?

geneeunit

it will fix your problems because everything will be connected correctly.. it plugs into a lot of stuff.. its the whole underdash harness... you see all the wires in the photo i posted? all of those.. minus the yellow srs harness, the floor harness, and the harness for the climate..


your options are like this:
-buy a 96-98 ex engine harness.. and swap out the 99-00 si one.
OR
-buy a 99-00 si underdash harness.. and swap out the 96-98 one..

B-outAteam

i had the same problem and i used the stock senser off the 99 civic trans and worked fine

amimaxima

I think im going to try to get my stock non vtec engine harness back and put that in and use a obd-2a ecu and run a wire for vtec

geneeunit

oh, yeah. thats right.. obd2a ecu. sorry, i was thinking you had an obd2b motor.

iamthefollower

yeah, it would be a lot easier just to get your stock harness put back on and run your wires for vtec.

amimaxima

the f@got I sold my sohc to wants 30 for the harness and he isnt even using it