OBDII Codes P0161, P0141 O2 Heaters

[jmoore]

I did a search and didn't come up with anything. The Service Engine Light came on and I got both these codes. They are P0161 O2 Heater, Bank 2 Sensor 2, P0141 O2 Heater Bank 1, Sensor 2.

The truck has 61K and I finished the 60K service myself a month or two ago. I think it's odd both would fail at the same time. The Rave CD said for both codes short/open circuit. Should I try checking the O2 connections or is there anything else I should check? Are new O2 sensors in order?

I did lightly spray the engine bay to get rid of salt, the night before I got the codes. Could that have contributed?

Also where do the O2 sensors connect to the harness? Again, I think it's weird both sides threw the code at the same time and they are both in the rear. Do the O2 sensor heaters have a fuse or relay?

Thanks in advance!

 

[jmoore]

Well, I crawled under there and saw where they plugged in, they couldn't have got wet with my spraying. Before I replace the O2 sensors, like I said, I wonder if there is a fuse or relay for the heater element.

 

[Chris-St Louis]

F2 Engine Compartment Fusebox.

 

[ptschram]

After you replace the fuse, you can climb beneath andlook for power on the heater circuit.If you have the Rave CD, you can find the colors for the various circuits.

Good luck. I have a truck telling me the rear O2 sensors aren't even connected and the vehicle is using "Inferred" data.

 

[jmoore]

Cool, thanks guys, I will check the fuse tomorrow. It does sound like a fuse is a likely culprit. I will let you know what I find out.

I appreciate the feedback.

 

[jmoore]

I checked fuse F2 and it was fine. Any other things to check?

 

[Chris-St Louis]

Water in the plugs

Did you unplug the O2s? May you got high pressure water in the plugs causing a short.

 

[jmoore]

Yeah, that's what I'm going to do next. I just went over to Atlantic British, (I live 5 miles from there) they suggested the same thing.

If it does fix the problem, with the codes go away or will they have to cleared?

Thanks for your help, Chris!

 

[Chris-St Louis]

A little of both.

OBD 2 Compliant care(96 and newer) will clear the codes if the problem doesn't reoccur for 50 warm up cycles.

That DOES NOT mean, starting and turning the car off 50 times.

What it does mean is 50 times going from a cold engine(Less then 100f) to a warm engine(200f) and back to less then 100. That is a cycle.

After 50 of those, the code goes away.

Or, you can clear it with a ODB2 Reader.

Disconnecting the battery WILL NOT clear a OBD Government mandated code!

 

[jmoore]

hmmm, this afternoon, sometime when I was out running around, my Service Engine Light turned off and hasn't come back on. Very strange.

 

[jmoore]

So, I"ve driven it a few more time and no more light. Does that mean the problem is all gone?

 

[Chris-St Louis]

No Light

No problem!

I'm guessing the water dried out, if it was somewhere.

I wouldnt worry about it..........

 

[jmoore]

Cool! Thanks Chris, I was about to plop down $150 on two new sensors, I guess I will now wait and see.

 

[jmoore]

Just as a follow up, the light came back on so I decided to suck it up and got new rear O2 sensors. $150. Tonight, I got under the snow drippy truck to change them out. I got the right rear unloose first. As it turns out, the wires to that 02 sensor apparantly were rubbing against the front drive shaft and got frayed. I cleaned them up, spliced them, and wrapped them up real good. I wire tied the wires out of the way. Fired he up, Service Engine light out! Woo Hoo!

 

[JUKE179r]

Old post... I know but I solved the same problem...

Myrtle ran sluggish. Smelled unburned fuel. Had Check Engine Light (CEL) and found 15A fuse F2 popped in V8 engine bay.
Grabbed Nanocom. Read 3 ECU fault codes:
P0141 - O2 Sensor Heater Circuit Malfunction b1s2 (left rear O2)
P0158 - O2 Sensor Circuit High Voltage b2s2 (right rear O2)
P0161 - O2 Sensor Circuit Malfunction b2s2 (right rear O2) - triggered CEL

Crawled underneath. Found b2s2/right rear/downstream O2 sensor wiring was rubbing against the front drive shaft.
Ordered a set of original NTK #25624 O2 sensors from Amazon at $25 a piece.
R&R'd the downstream O2 Sensors with a large adjustable wrench. Repositioned new O2 wiring away from moving and sharp edged parts. Replaced V8 engine bay 15A fuse F2. Cleared fault codes. Cleared adaptions. Went for a test drive.
Problem solved.