Hey guys,

Here is the setup first of all:
Car: 92 CX civic hatch
Motor: 96 usdm GSR
Engine Harness: 96 usdm GSR
ECU: JDM GSR P72

Here is the problem:

I was running the car on a chipped P28 (type R map), until I was able to track down an obd 1 GSR ecu. Well I got a good deal on an obd1 JDM GSR ecu. I knew I would need to wire up the IAB (a17) and Knock (d3) so I went ahead and got those taken care of. When I fire it up I have a CEL (code 41 heated O2 sensor).


I figured maybe I knocked something loose while doing my wiring so I checked the O2 plug engine harnes side and O2 sensor side. All was good. Checked the ECU plugs cause I was wiring down there. All 4 of the O2 sensor wires are nice and snug (A6...heated O2 wire,A25,D14,D22).

Maybe the O2 was bad....well I changed it with an O2 that is in perfect working order and still the code pops up with the JDM GSR ECU.

Here is the strange thing, When I hook up my P28 the CEL goes away. It's always possible that the JDM GSR ECU is fried, but in all my time workin on hondas I've never actually seen a fried ECU.

Does anyone have any suggestions , is this a common issue with JDM GSR ecu's? Also is there anything else that can trigger a CEL for code 41 other than the O2 itself?

Thanks in advance guys!!!

 

it possible that the driver for the O2 heater is fried, it's not as difficult to damage that output as some people think.

It's also possible that the P28 has the O2 heater disabled, which is very common in "typeR" chips. (everything is disabled, no idea how that makes it a typeR, but some people think it does)

A multi-meter and some time is your best tool.
volts, make sure there is 12V ignition power on one of the black wires.
ohms, make sure A6 is connected to the other black wire.

NOTE: A25 is not directly connected to the heater's power. (electrically, yes, directly, no)
The O2 heater is connected to the junction on the driver's shock tower, which is connected to the main relay output, that is connected to A25/A1.

D14 and D22 is unrelated.

 

Thanks alot man....If it stops raining today i'll pop the hood and check the currents.

I forgot to mention this also but the other night my friend was gonna buy a P75 from someone to get his car running...long story short I put the computer on my car to make sure it worked and I threw NO CEL's on a stock P75

That would lead me to belive its not the O2....but i'm still going to check the stuff Relic1 stated.

In the mean time does anyone have anymore suggestions?

Thanks guys...


Modified by WhiteNess at 10:52 AM 8/20/2008

 

did you try hardwiring to the ecu the o2 sensor??? Is there another stock ecu you can borrow from someone?? chances are your chipped p28 has o2 disabled

 

No I didn't hardwire the O2 (I hate cut up harneses haha).

And no luck on the multimeter, somehow it got smashed in my toolbox.

I did try my friends P75 the other night and it threw no CEL's and that was a stock ECU. Maybe the O2 was being nice that night....

I can get my hands on several stock ECU's, i'm guessing that will be my next plan of attack. I have just never delt with a JDM ECU before, and didn't know if this was a common thing with JDM ECU's. Or if maybe this was a common thing when wiring up the knock and IAB on a GSR. Live and learn. I might have to just break down, quit being cheap, and buy a new O2 haha


Thanks for the advice...and keep the ideas coming, never hurts to try something

 

Ok we have an update....

I borrowed a friends STOCK obd1 usdm P72.....I threw no CEL's, I hit vtec, but no IAB's since mine are set up for the reverse polarity of the JDM P72

Long story short, my JDM P72 is screwed up....does anyone know how to reinstall a driver?...i'm guessin its not like hooking up a printer on windows haha

I also opened up the computer and found A6 wich is the pin for heated O2 wire. I traced the pin on the motherboard as far as I could and there were no problems that I saw. The computer looks clean all over.

Thanks and keep the ideas coming

 

its your o2 sensor man. it comes on because you dont have one on or your old one is bad. good luck man

 

*blink* you do realize this is a 2 year old thread right?