NOOdS

2000 civic cx hatch
2000 b18c1
obd2a ecu with jumper harness

i tried to smog my car the other day and i failed because my ecu couldnt be read by the smog machine. so i borrowed my buddies obd2 code reader to check for myself, and it said cannot communicate with the ecu. i dont understand because when i got the motor barred, the reff said the jumper harness was okay to have and passed me. so now i have questions and hopefully someone can help out. check engine light is not on.

1. is code reader supposed to able to read an ecu using a jumper harness?
2. can the jumper harness be the issue(ebay brand)?
3. can it be the ecu? (as far as i know, i was told its a virgin p72)
4. is it possible to pass smog with a jumper harness?


thanks

itll be so much easier if i can just find someone to remove the immobilizer from my obd2b p72. thats why i had to use a obd2a instead.

Former User

Is hood fuse 43 blown?

NOOdS

all the fuses seem to be fine under the hood, no blown fuses. which one is fuse 43 that you were talking about?




by the way, i tried using another obd2a p72 ecu to see if it might be able to read in my car, but still nothing. so now im thinking it might be the ebay jumper harness? or could it be something else? i dont know anyone else that has another jumper harness to try out, and dont really want to spend 100+ on something that might not be the problem.

Former User

Fuse 43 = 7.5A fuse labeled interior light.

NOOdS

oh okay, well that fuse is fine.

ive just called my machanic and he told me that it could be my jumper harness since its a cheap ebay one. he said sometimes those cheap harnesses dont have the data link wire so it doesnt let you read the ecu. but i was thinking, shouldnt they make all jumper harnesses be able to be read by the scanner tools? well, anyways ill have to take it to him to pin in a wire for that tomorrow, if thats the issue. is there anything else i can do to trouble shoot the problem?

92lxsleeper

btw your gonna fail anyway. you have to have obd2b for that car.

grumblemarc

iTrader: (4)

He'll probably fail as soon as they see the harness.

Former User

Check whether the DLC (where code reader plugs in) gets voltage from fuse 43 and has good ground on the black wire terminal.

Check whether the wire that runs from the DLC to the ECU has continuity and no shorts.

NOOdS

Well, I passed smog today. I proved some of you guys wrong.

After a whole day of tracing wires, I found out my jumper harness was good. I ended up trying a obd2a civic ex ecu, and the code reader detected it, but not the gsr. I used that obd2a ex ecu with my jumper harness to smog and it passed. I tried the gsr ecu in another civic and it doesn't detect. now I'm curious to try the gsr ecu in a integra to see if it reads, because I've tried another gsr ecu and it doesn't in my car.

apexi_rsx

is the GSR ecu a JDM ecu????? if so this is your problem they dont use the data port.

grumblemarc

iTrader: (4)

Not that I believe you when everything I read stated otherwise, but if you passed, then problem no longer exists.

See above post. If you neglected to mention this detail it would explain everything.

NOOdS

its a usdm gsr ecu, i also mentioned that i tried using another usdm gsr ecu(came out of a 98 gsr). both couldnt be detected. well, thanks for the inputs. the problem still exists with the gsr ecu not being able to read in my civic. but the main issue was to pass smog, and i was able to pass with an obd2a ex ecu. so im happy. im using my tuned p28 now. i will probably try to figure it out again later if i have to need to. thanks

Former User

There's only one difference between the data link connector (DLC) circuits for the OBD2a Civic EX and Integra GSR. The latter has one DLC terminal (Brn/Blk wire) that shares the G101 ground with ECU A9 and A22.

OBD2a GSR:



OBD2a Civic:

NOOdS

thanks ron

but do you have a diagram for the obd2b civic also?

Former User

It's wired similarly to the OBD2a Civic (where K-line pins to ECU C8), except that DLC communication with the ECU (K-line) pins to A21 for the OBD2b ECU. Your OBD2b-OBD2A jumper harness would presumably address this issue.

OBD2b Civic:

NOOdS

ron, you have everything. thanks

i guess ill see if adding that ground will work.

rreed

found this thread in my search to fix my 2001 civic ex 5spd.after my testing looks like my ecu is out due to cranking on a weak battery with a jumper box.first batt light was on solid even though grounds where good and alt was charging.after doing guage cluster self test,started car it ran for a few minutes then died,no comm with scanner,flashing key light,etc.i opened ecu and i dont see any damage.question is @ronj@ht,i see in this thread its possible to use a different ecu and still pass smog?what are my cheapest options to get this car going again.i found a cheap ecu same as whats in it,and looks like i can get a honda interface module to work with my laptop,they say it will program ecu and imobilizer keys for 132.00.is this gonna be my best option?or is switching to an earlier ecu with out imobilizer a better bet?thanks for any input.