# O2 sensor, check engine light on **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** accord, honda\ **Created:** [November 26, 2023, 5:30am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919 "2023-11-26T05:30:38Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![thefinisher1985\_185383](https://avatars.discourse-cdn.com/v4/letter/t/f6c823/32.png) [@thefinisher1985\_185383](https://community.cartalk.com/u/thefinisher1985_185383)\ **Post date:** [November 26, 2023, 5:30am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/1 "2023-11-26T05:30:38Z")
Hi i have a 2004 Honda Accord LX with 190,000 miles and oh boy I feel I keep having trouble from time to time too often. So I have a code p0141 for the heater circuit or whatever, the O2 sensor. So when I called to get the part they asked if it was upstream or downstream. Is there a way I can find this out myself or do I have to do the thing I don’t want to and take it to a shop and pay 100 Dollars just to find out that specific thing? ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [November 26, 2023, 5:39am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/2 "2023-11-26T05:39:51Z")
> **[P0141 OBD-II Trouble Code: O2 Sensor Heater Circuit Malfunction (Bank 1,...](https://www.yourmechanic.com/article/p0141-obd-ii-trouble-code-o2-sensor-heater-circuit-malfunction-bank-1-sensor-2-by-jay-safford)** > > P0141 code definition O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2) What the P0141 code means P0141 is the OBD-II generic code indicating the Engine Control Module (ECM) has tested the O2 sensor heater circuit and... Sensor 2 means it’s the down-stream sensor. Tester ---
**Author:** ![thefinisher1985\_185383](https://avatars.discourse-cdn.com/v4/letter/t/f6c823/32.png) [@thefinisher1985\_185383](https://community.cartalk.com/u/thefinisher1985_185383)\ **Post date:** [November 26, 2023, 6:03am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/3 "2023-11-26T06:03:54Z")
Hey appreciate that. Is there an app to this as well or just the site? ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [November 26, 2023, 2:14pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/4 "2023-11-26T14:14:06Z")
You can download Torque Pro and other apps to read OBD2 codes if you buy the Bluetooth reader they recommend ($20 or less). If it finds a code, it will link you to the description of the code. However, most parts stores will read the codes for you and tell you what they say. That doesn’t mean that’s what is wrong… counter people at auto parts stores are salespeople, NOT mechanics. ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [November 26, 2023, 10:24pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/5 "2023-11-26T22:24:05Z")
> [@thefinisher1985\_185383](#): > > Is there an app to this as well or just the site? Try Googling “p0141”. Some of the links don’t say which sensor it is, some do. Most offer an explanation what it means. Some u-tube vdos in the search results even claim to show how to diy’er fix it. Suggest to watch a few, probably something in those you’ll find instructive. The Autozone link doesn’t seem to say, but the “Your Mechanic” link says it is bank 1 sensor 2. V-configured engines have two exhaust banks, in-line engines (I) only have one. Bank one would presumably correspond to the number one cylinder. By convention sensor one is before the cat, sensor 2 after the cat, downstream… ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [November 26, 2023, 10:29pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/6 "2023-11-26T22:29:07Z")
> [@thefinisher1985\_185383](#): > > I don’t want to and take it to a shop and pay 100 Dollars just to find out that specific thing? I expect most shops would agree to apply that sort of diagnostic fee toward the final repair bill, provided they did the repair. Suggest to ask. They’ll of course have to bill you a diagnostic fee if you don’t use them for the actual repair. It’s possible the fix doesn’t require the sensor be replaced, could be a minor wiring or connector problem. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [November 26, 2023, 10:43pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/7 "2023-11-26T22:43:26Z")
> [@thefinisher1985\_185383](#): > > I don’t want to and take it to a shop and pay 100 Dollars just to find out that specific thing? Do you refuse to pay your MD’s fees for diagnosis? If so, you may find it difficult–or impossible–to find further medical care. While mechanics might not necessarily be as sophisticated as modern medical entities, the bottom line is that failure to pay your bills could result in deprivation of services in the future. A service provider needs to be compensated for his services, whether he/she is a medical profressional, or a professional mechanic, or a plumber, or an electrian, or… whatever. ---
**Author:** ![davesmopar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/davesmopar/32/41750_2.png) [@davesmopar](https://community.cartalk.com/u/davesmopar)\ **Post date:** [November 27, 2023, 1:31am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/8 "2023-11-27T01:31:45Z")
> [@George\_San\_Jose1](#): > > V-configured engines have two exhaust banks, in-line engines (I) only have one. Bank one would presumably correspond to the number one cylinder. Some, maybe most/all, OBD2 inline 6 engines will/can have an O2 sensor for 123 cylinders and one for 456 cylinders, so in that case bank1 would be for 123 cylinders and bank 2 would be for 456 cylinders, and bank(?) sensor 1 or 2 would be the same way… ---
**Author:** ![thefinisher1985\_185383](https://avatars.discourse-cdn.com/v4/letter/t/f6c823/32.png) [@thefinisher1985\_185383](https://community.cartalk.com/u/thefinisher1985_185383)\ **Post date:** [November 27, 2023, 5:44am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/9 "2023-11-27T05:44:07Z")
Sucks cause I already bought the downstream 02 sensor and I can’t get in touch with my mechanic. Hopefully he responds soon. I mean I could get it checked at a shop and see what they tell me and then I can see if it’s something I can fix myself. ---
**Author:** ![thefinisher1985\_185383](https://avatars.discourse-cdn.com/v4/letter/t/f6c823/32.png) [@thefinisher1985\_185383](https://community.cartalk.com/u/thefinisher1985_185383)\ **Post date:** [November 27, 2023, 5:45am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/10 "2023-11-27T05:45:06Z")
I just meant it sucks cause I’m really hoping it was the right one. And my car is 2.4 liter engine ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [November 27, 2023, 5:57am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/11 "2023-11-27T05:57:33Z")
The most common reason for a P0141 code is, the heater in the O2 sensor is damaged. And this is usually caused by thermal shock. You replace the O2 sensor first. And if that doesn’t fix the problem. then you’re looking at a problem in the wiring or the computer. And now you’re talking major diagnostics and money. Replace the sensor. Tester ---
**Author:** ![thefinisher1985\_185383](https://avatars.discourse-cdn.com/v4/letter/t/f6c823/32.png) [@thefinisher1985\_185383](https://community.cartalk.com/u/thefinisher1985_185383)\ **Post date:** [November 27, 2023, 1:06pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/12 "2023-11-27T13:06:48Z")
I have the sensor, and I bought the downstream one, it was said that’s the one I need and i really hope so. But i also seen a video that shows a lot of times it’s just a blown fuse. Google says my heater sensor fuse is under the hood and is number 21 but I don’t see any number 21. Would my Manuel tell me which fuse number it is? ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [November 27, 2023, 1:29pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/13 "2023-11-27T13:29:33Z")
> [@thefinisher1985\_185383](#): > > I can see if it’s something I can fix myself. ![image](https://global.discourse-cdn.com/cartalk/original/3X/2/2/2207a2dfc447f40d003fce03bcb69dfb50638d03.png) ---
**Author:** ![davesmopar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/davesmopar/32/41750_2.png) [@davesmopar](https://community.cartalk.com/u/davesmopar)\ **Post date:** [November 27, 2023, 2:50pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/14 "2023-11-27T14:50:09Z")
> [@thefinisher1985\_185383](#): > > I have the sensor, and I bought the downstream one, What brand did you buy? and was it an exact fit or universal?? ---
**Author:** ![thefinisher1985\_185383](https://avatars.discourse-cdn.com/v4/letter/t/f6c823/32.png) [@thefinisher1985\_185383](https://community.cartalk.com/u/thefinisher1985_185383)\ **Post date:** [November 27, 2023, 7:11pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/15 "2023-11-27T19:11:41Z")
I believe it was boesher or something like that and I told them my exact vehicle information so I’m assuming an exact fit but I’m waiting on my mechanic to see if it’s the piece I need. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [November 27, 2023, 7:20pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/16 "2023-11-27T19:20:50Z")
I think you mean Bosch. [https://www.google.com/search?client=firefox-b-1-d&sca\_esv=585680499&q=bosch+o2+sensor&tbm=shop&source=lnms&sa=X&ved=2ahUKEwj4rd7o8uSCAxWTIDQIHbIuCxkQ0pQJegQIDRAB&biw=1366&bih=579&dpr=1#spd=13444151630540290421](https://www.google.com/search?client=firefox-b-1-d&sca_esv=585680499&q=bosch+o2+sensor&tbm=shop&source=lnms&sa=X&ved=2ahUKEwj4rd7o8uSCAxWTIDQIHbIuCxkQ0pQJegQIDRAB&biw=1366&bih=579&dpr=1#spd=13444151630540290421) Tester ---
**Author:** ![davesmopar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/davesmopar/32/41750_2.png) [@davesmopar](https://community.cartalk.com/u/davesmopar)\ **Post date:** [November 27, 2023, 9:33pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/17 "2023-11-27T21:33:38Z")
I would return it and buy a OE Denso or NGK… ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [November 27, 2023, 9:36pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/18 "2023-11-27T21:36:18Z")
The heater is just a resistor. 10-30 ohms would produce 5-10 watts of heating, seems about right. If you know how to measure resistance, you could compare the new one to the old, resistance-wise. You’d need to know which connector pins are used for the heater. Your best bet toward a quick solution is to hire a well-recommend experienced mechanic to at least diagnose the problem. Then you could replace the part yourself if you wanted. ---
**Author:** ![weekend-warrior](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/weekend-warrior/32/26122_2.png) [@weekend-warrior](https://community.cartalk.com/u/weekend-warrior)\ **Post date:** [November 27, 2023, 10:07pm UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/19 "2023-11-27T22:07:15Z")
Check the number 4 fuse under the dash to see if is good. [2004 Honda Accord Fuse layout — Ricks Free Auto Repair Advice Ricks Free Auto Repair Advice | Automotive Repair Tips and How-To](https://ricksfreeautorepairadvice.com/2004-honda-accord-fuse-layout/) ---
**Author:** ![thefinisher1985\_185383](https://avatars.discourse-cdn.com/v4/letter/t/f6c823/32.png) [@thefinisher1985\_185383](https://community.cartalk.com/u/thefinisher1985_185383)\ **Post date:** [November 28, 2023, 4:36am UTC](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919/20 "2023-11-28T04:36:51Z")
@davesmopar it is actually a denso I thought it was something else. [Next page](https://community.cartalk.com/t/o2-sensor-check-engine-light-on/193919.md?page=2)