Dubwhat

Getting this on the GT. New O2 sensors. Where to start looking? Anyone explain to me how this system works?

I looked at my manuals and I don't find anything on it, at least not so far. I do have to do a bit more digging.

Any help would be appreciated.

cliffyk

Here are the P0135 possible causes and diagnostic tips from the shop manual.

Bank 1 is the passenger side, sensor 1 is the front sensor.

All four O² sensor heaters are powered through the same fuse so that would not be the problem (you would have more codes), so inspect the wiring and connector for shorts or open connections.

It could also of course be that the heater in that sensor is defective. You can check the heater resistance with a multimeter, it should be 3.3Ω (disconnect it before testing). If you have the OEM sensor then the heater wires for HO2S-11 will be red/yellow and white/black. If the sensor was replaced with an aftermarket unit the heater wire will most likely both be white...

Dubwhat

I replaced the front 2 O2's about three weeks ago. I didn't get the error unless I was running a KOEO test....now my CEL is on because of a DPFE High Output code (P1401), and when I pull the codes, I get the O2 heater circuit error.

I will have to check the harness to see what it looks like.....their NGK O2 sensors, so the wires are as such,

http://www.ngksparkplugs.com/tech_su...wirecolors.asp


This is rather annoying. I don't wanna shell the harnesses and chase wires =(

cliffyk

Yup--NGK has the same colour wires as Bosch and many other aftermarket sensors:



Are you getting DTCs for just one O² sensor, or more than one?

Dubwhat

Just the one o2 sensor. The Passenger side (Bank 1) o2.....'

What's weird is I drove it this morning, after clearing the codes, and the only code I got was for the DPFE.....there wasn't a code for the O2 heater, tho I wonder if that's a soft code.