Crank sensor help

[slimm]

alright. its time for me to get my tag and my CEL is on. i have a 98 civic running a d15b (obd2). I had an o2 sensor code, fixed. and now i have the crank sensor code. i put a brand new sensor on this morning and, of course, its still giving the same code, otherwise i wouldnt be writing this. i havent had a chance to meter the wires to see if there is a signal getting to the ecu b/c i have to go to work. what are the chances that my harness is indeed messed up and the signal isnt making it to the ecu. if thats the case, how wise would it be to me to wire it directly to the ecu? thats what i had to do for my o2 sensor. one last thing. if i do have to straight wire it, where does the middle wire go? im thinking a 12v source connected to the ignition circuit only b/c i had to do that with the o2 sensor. i cant really tell what color the wire is. its either black and red or dark blue and red. if i could get alldata, i wouldnt be having this problem. anyhoo, all help is appreciated.

[Tech5]

did you clear the code out once you fixed it>?

[slimm]

did you clear the code out once you fixed it>?
yea. cam back on after about one second after i started it back up.

[slimm]

wow. no one?

[Tech5]

Sounds like something to do with wiring or bad ecu.... Most causes its the sensor , but if you installed a NEW one then I would check the P&G&.5volt reference ... then ecu would be next

[dallasb84]

no you cant just wire it up like that....

the sensor has power ground and sometimes shielded ground....

if you wire the shielded ground into ground it will pick up noise and throw a cel.

you have to use the signal ground from the coax metal shield and run that to ground..

colors should be red blue blue/white.... black then white black and white blue.... in any case you need to get a wiring diagram and make sure you keep power to power ground and shield to ground and signal ground to ecm.

it took me around 3 hours reading wiring diagrams from obd2 integra and obd2 civic to get it right..... as well as having to draw a shematic and use my brain to make it work...


you could try the ckf trick but it is hit or miss with a cel


im talking about the ckf sensor (crank sensor)

[xdavidscenex]

safe way is just buy a new harness sounds like yours is messed up anyway but id check it with a meter first to eliminate harness or ecu.

[slimm]

no you cant just wire it up like that....

the sensor has power ground and sometimes shielded ground....

if you wire the shielded ground into ground it will pick up noise and throw a cel.

you have to use the signal ground from the coax metal shield and run that to ground..

colors should be red blue blue/white.... black then white black and white blue.... in any case you need to get a wiring diagram and make sure you keep power to power ground and shield to ground and signal ground to ecm.

it took me around 3 hours reading wiring diagrams from obd2 integra and obd2 civic to get it right..... as well as having to draw a shematic and use my brain to make it work...


you could try the ckf trick but it is hit or miss with a cel


im talking about the ckf sensor (crank sensor)
thanx for your input. the wires dont have shielded grounds. checked em already. i tried the lil wiring trick and it didn't work either. i know the wire colors and where they go on the ecu except for one wire and if im not mistaken, that one wire goes to ignition 12v but im not sure. i was hoping someone on here could confirm that for me. so far, no one has. im tryna get in contact w/ a friend of mine so i can get on alldata but, infortunatly for me, hes on vacaton (the bastard).

[Tech5]

bad ecu

[green91]

Put an oscilloscope on the wiring at the ECU for ckp and give us a screen shot of the signal.

[slimm]

Put an oscilloscope on the wiring at the ECU for ckp and give us a screen shot of the signal.
and you're serious...

[teh_mugen18]

and you're serious...


AllData has a thing where you can actually do something like that, idk if its exactly an oscilloscope though, but it basically is realtime data logging but it comes up as a graph and analysis can be made from that. I've seen it at work lol when i used to work at the GM dealership :o


diagnosticians are ftmfw :cheers:

[dallasb84]

jeesus christ.......


lets start over..

is this a swap, what ecu, what wiring harness, obd1 or 2, how many wires are coming out of plug....

[green91]

While i wasnt being completely serous since most people don't have an oscilloscope, they are the proper way to test a crank sensor.

[slimm]

jeesus christ.......


lets start over..

is this a swap, what ecu, what wiring harness, obd1 or 2, how many wires are coming out of plug....
i said in the begining that this was an abd d15b. if you know your civics, you know that a civic wasnt available in the states with a d15b in 98 so clearly its a swap. i also metioned that there a 3 WIRES. i also said that this has a y8 ecu. i didnt mention the specifics of the ecu. MY BAD. its a p2p ecu. i mentioned all data b/c that would tell me where that last wire goes that i was talking about. i also didnt mention what harness. MY BAD again. i have the ex coupe harness.

[slimm]

While i wasnt being completely serous since most people don't have an oscilloscope, they are the proper way to test a crank sensor.
thats wasup. i dont even know where to buy an oscilloscope. i did test the wires and there is no signal traveling throughout. i didnt have time to finish b/c i had to do a bit of christmas shopping. im gona finish my trouble shooting tomorow. im pretty sure theres a break in the wiring between the sensor and the ecu and rewiring would solve it. i just hope im right. i gotta get my tag friday and i REALLY dont feel like paying "the price" for a frikkin emisions test. ya dig?

[Tech5]

thats wasup. i dont even know where to buy an oscilloscope. i did test the wires and there is no signal traveling throughout. i didnt have time to finish b/c i had to do a bit of christmas shopping. im gona finish my trouble shooting tomorow. im pretty sure theres a break in the wiring between the sensor and the ecu and rewiring would solve it. i just hope im right. i gotta get my tag friday and i REALLY dont feel like paying "the price" for a frikkin emisions test. ya dig?

Snap on I have one But I paid a penny for mine

[dallasb84]

ok you need to do a ckf splice..... unfortunately i could not find anywhere online for instructions for the splice...... but i found hundreds of places that do the bypass.....

heres what i ran into....

the grounds and power DO NOT go from ecu to sensor.... so you cant just run a wire like that...... instead they are in the injector circuit...... at least pulling power....

next thing i noticed is the coaxial ground (shielded ground is connected to the shielded ground that feeds all the other sensors) needs to be spliced in somewhere.

what you need is the d15b wiring diagram for the ckf (i didnt think jdm motors had them, i thought they have a cps inside the dizzy).

and the wiring for the ckf d16y8 and compare circuit..... and tie them in accordingly....

thats how i got my ckf splice accomplished for my b18b in my 98 civic ex....


but if your jdm motor does not have the ckf sensor..... your kinda fucked because the p2p is looking for sensor output...... but..... i believe the fuel pump pressure sensor guy runs off a 5 volt signal and might actually work for a ckf trick as well......

what youll need is to find a sensor output to mimic the cel thats poping up....

[slimm]

i found the bypass on rywire last night when i got home. it worked beautifully. thanx for all of your help guys!