twice in one week i throw myself at the mercy of the tech forum. i suck.

car: 96 ex coupe with 99 b16a2. p2t ecu, 96 ex wiring harness modified.

with the exception of an intermittent secondary o2 sensor issue, everything has run fine for 2+ years. i went to get my car smogged this week, and the shop hooked up their obd2 scanner to my data link connector. apparently after several tries they could not get a reading - 'no communication' was their claim.

my helms doesn't help trouble shoot the dlc, so i did some of my own:

-i visually inspected the connector. there are only five wires (that's all there should be), all of which are firmly attached, and are not spliced into/cut all the way up to the main harness.

-i checked the engine bay fuse #43 which is good. my ceiling light and trunk light have always worked.

-i checked and received voltage at the white/red wire (12+/-) and on eof the blue wires (5+/-), both black wires are grounded. there is a blue/green wire that i get nothing from.

-the check engine light works just fine, and was not on when the car was tested.

i am going to bring it to another shop this week and see if they can read it, or have them figure out why they can't, but i don't put much faith in any shop. anyone ever experience this? anyone shed some light on this?

 

>>>help<<<

 

I am currently going through the same goose chase. I have OBD 1 equipment in a 99 OBD2 car. Same error reading. I have talked to friends that have had this problem and the smog station simply passed the car because of the long lines behind them. I don't know what to do. If you get any further information, please let me know.

 

An obd2 scanner will not read OBD1 codes. Different communications.

should try jumping SCS connector to see if can flash codes on MIL

 

after reading the helms some more, there is a blue/yellow (i believe yellow) wire that should be pulsing voltage. i think that was the wire that i wasn't getting anything from at the connector. i will test that wire at the ecu this week to see if it's any different there.

the smog claimed that 2 years ago (in california) it wasn't required to get a readin at the obd2 connector, and that it is now.

and the cel is definetely working 100%.