Check engine light - P2195 and C1241 codes...new battery fixes it?

So Gramps ('05 DC) and I were coming back from fishing the other night and the check engine light comes on. I plugged in at Autozone today and got codes P2195 (Powertrain system - Oxygen sensor signal stuck lean) and C1241 (ABS - Low battery positive voltage or abnormally high battery positive voltage). Didn't recall how old my battery was but I did see quite a bit of white powder, corrosion crap on the battery. Not knowing whether install of the oxygen sensor was idiot proof, I held off on buying the sensor but bought a new battery. To my surprise, when I got home and installed the battery, the check engine light was cleared. Time will tell if this was just a battery issue, but thought this information might be useful to somebody at some point.

 

If you leave the negative battery cable off for 5-10 minutes it's common for the codes stored in the ECU to clear. I'd only be worried if they return.

 

Yeah, the "fix" was short lived. Check engine light came back on after a few miles of driving. Guessing I'm in the market for a sensor. Interested in info on degree of difficulty of replacing the sensor before I head down that path.

 

Same 2 codes ?

Depends....according to what it looks like underneath rust wise. If things are decent under there, the rears are fairly straight forward. You'll know once you see condition.

Since the P2195 is B1S1, meaning front sensor driver side, it gets a little more difficult. The Yota engineer was good on most our 1st Gen designs but had too much Sake when designing front sensors !

The below is driver side rear sensor of someones 1st gen. That is not my definition of decent shape and would require more than just a sensor possibly.

 

FWIW, all kinds of strange stuff happens happens to Toyotas when the voltage gets flakey...check your alternator.

 

05 uses a threaded in sensor. Denso part number is

$124 234-9051 Right-Bank Upstream with 4-Wire 8.5” Option Air Fuel Ratio Oxygen Sensor

234-9051, and is what you get in a red and white box at a higher price if you buy from a dealer. And you will want to use a Denso sensor.

It’s been a while, but I want to say this style of O2 sensor socket and a long handle flex ratchet made it happen. It’s a bit of a tight spot, but not terribly hard if it’s not badly seized in the bung.

 

Thanks for all the info/responses. I won't be able to take a look for a few days, but I'll report back. Hoping it's not the alternator as well, but at 293k miles, I won't be surprised if it's time for a new alternator too.

 

My alternator lasted 16 years, ~66k miles. It wouldn't be unheard of for that to be the issue. There are a number of tests you can do to check it out.

While in there, replace with a green Gates HD serpentine belt. Replacement Denso alternators are relatively cheap! Go ahead and get one of the 130A units, if you don't already have one.