Forums Forums (
-   S-Series Tech (
-   -   P0141 Code Will Not Go Away! (

sr20fd3st 10-28-2009 11:13 AM

P0141 Code Will Not Go Away!
Car is 99 SW2

Code is for heater circuit malfunction in the after-cat heated O2 sensor. It is the ONLY code.

I replaced the O2 sensor, and checked the EGR fuse. Fuse is fine. Code still came back on.

What other causes are there for this code? I need to pass an emissions check...2 weeks ago.

Any help would be much appreciated.


jcasekim 10-28-2009 12:14 PM

Re: P0141 Code Will Not Go Away!
This is an obvious question, so please don't get mad! But you replaced the post-cat O2 sensor under the car, not the exhaust manifold sensor under the hood, right? Is it possible the wire harness wasn't plugged back in tightly, or that one of the wires to the post-cat sensor (I think there are 3 or 4 wires) is damaged?

I once removed and reinstalled my rear (post-cat) O2 sensor (using the same old sensor) and it was not easy. I had trouble disconnecting the wiring harness, then I disconnected the downpipe and cat so I could set them on the garage floor without worrying about knocking my car off the jackstands. Slipped a 22mm combo wrench over the wiring tail and onto to O2 sensor. Then I put one foot on the cat and really had to pull hard to loosen the sensor. Removing the front O2 sensor was a lot easier, especially with the exhaust manifold warm.

sr20fd3st 10-28-2009 12:24 PM

Re: P0141 Code Will Not Go Away!
I still need to check the wiring I guess. The Sensor is new. I have my own exhaust with a new O2 boss that easily locates the sensor for easy removal. Has a brand new Cat also. I know the sensor is good. Besides the sensor, or the wiring to the sensor, or the EGR fuse, what else could cause this code?

sr20fd3st 10-29-2009 08:07 PM

Re: P0141 Code Will Not Go Away!
Bump? I am desperate!

OldNuc 10-29-2009 08:34 PM

Re: P0141 Code Will Not Go Away!
In the socket that the rear O2 sensor plugs into check for the presence of 12vDC with the key on. The heater power is on the pink and dark green wire. The heater current is controlled by the PCM through the dark green wire. The pink wire is direct from teh UHJB and is the 12vDC + power source. There are 2 tan wires and a black/white wire located on teh rear left end of teh block above the starter and just below the intake manifold. Verify that both tan wires are connected. These are the PCM grounds for the O2 sensors.

sr20fd3st 10-29-2009 08:39 PM

Re: P0141 Code Will Not Go Away!
awesome, thanks! will check it out tomorrow when light comes back from over the horizon.

Should the voltage be there just when running or also at just Key On?

OldNuc 10-29-2009 10:26 PM

Re: P0141 Code Will Not Go Away!
Key in the RUN position but engine off and you will have 12vDC on the Pink wire. Check Pink to Dk. Blue and Pink to the battery negative, do both checks. There is no easy way to test the PCM grounding circuit except to check for the Tan wires on the left rear corner of the block. You can see them from above after the air induction tube is off. If you have the 12vDC Pink to the battery but not when you check Pink to Dk. Blue it is a problem with the PCM grounding current control wiring.

sr20fd3st 10-31-2009 01:41 PM

Re: P0141 Code Will Not Go Away!
Awesome. The pin for the pink wire in harness connector was completely corroded (others were fine) It was just a green clump of crap in that pin. Took wires out, put new pin on pink wire, put back in connector, connected to new 02 sensor. No More Code. Drove the piss out of it, got Catalyst Ready to show on my scanner, passed E-Check. Hurray!

OldNuc 10-31-2009 03:17 PM

Re: P0141 Code Will Not Go Away!
This is good!:D

All times are GMT -4. The time now is 05:07 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc. The Saturn Enthusiasts Site.