# 02 sensors **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** sierra2500, exhaust-system, gmc\ **Created:** [October 19, 2020, 8:41pm UTC](https://community.cartalk.com/t/02-sensors/171374 "2020-10-19T20:41:35Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![natewenger9\_171681](https://avatars.discourse-cdn.com/v4/letter/n/ecae2f/32.png) [@natewenger9\_171681](https://community.cartalk.com/u/natewenger9_171681)\ **Post date:** [October 19, 2020, 8:41pm UTC](https://community.cartalk.com/t/02-sensors/171374/1 "2020-10-19T20:41:35Z")
I had three 02 sensor codes up for the bank2 sensor2 on my Sierra. I replaced the sensor and immediately had all three come back along with the same three counterpart codes for bank1 sensor1. Does anyone have any idea what could have caused that? ---
**Author:** ![eddo](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/eddo/32/2594_2.png) [@eddo](https://community.cartalk.com/u/eddo)\ **Post date:** [October 19, 2020, 10:03pm UTC](https://community.cartalk.com/t/02-sensors/171374/2 "2020-10-19T22:03:49Z")
post the actual codes you got. Before the repair, and now after the repair. also tell us year & mileage of this GMC Sierra ---
**Author:** ![natewenger9\_171681](https://avatars.discourse-cdn.com/v4/letter/n/ecae2f/32.png) [@natewenger9\_171681](https://community.cartalk.com/u/natewenger9_171681)\ **Post date:** [October 19, 2020, 10:44pm UTC](https://community.cartalk.com/t/02-sensors/171374/3 "2020-10-19T22:44:41Z")
It’s an 06 Sierra 2500hd approaching 180k miles. I had p0056 p0060 and p0161 up, which are all for bank2 sensor2 if I’m not mistaken. After I replaced the sensor those codes came back immediately except for p0060 which came back after a few start ups. Also immediately I had p0030 and p0135 for bank1 sensor1. Afterwards a third code came up for bank1 sensor1. I can’t think of those numbers right now but it was a heater resistance code. Basically the counterpart of p0060. I knew it might be a wiring issue before I started but decided to take a chance and replace the sensor. What I’m trying to understand is why changing it caused the same problems on bank1 sensor1. ---
**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:** [October 19, 2020, 11:15pm UTC](https://community.cartalk.com/t/02-sensors/171374/4 "2020-10-19T23:15:22Z")
Have you checked to see if the 15 amp heater fuse for the o2 sensor has blown? Tester ---
**Author:** ![natewenger9\_171681](https://avatars.discourse-cdn.com/v4/letter/n/ecae2f/32.png) [@natewenger9\_171681](https://community.cartalk.com/u/natewenger9_171681)\ **Post date:** [October 19, 2020, 11:17pm UTC](https://community.cartalk.com/t/02-sensors/171374/5 "2020-10-19T23:17:06Z")
I did and it looked fine. Although I have to admit I wasn’t exactly sure how to know if it’s blown. ---
**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:** [October 19, 2020, 11:20pm UTC](https://community.cartalk.com/t/02-sensors/171374/6 "2020-10-19T23:20:25Z")
![image](https://global.discourse-cdn.com/cartalk/original/3X/c/d/cd0e245f6d4496f1c3965124133845cc0f1d6b93.jpeg) ![image](https://global.discourse-cdn.com/cartalk/original/3X/b/e/bee6fcf681c8fbc18657216acd508fa1361b8190.jpeg) Tester ---
**Author:** ![natewenger9\_171681](https://avatars.discourse-cdn.com/v4/letter/n/ecae2f/32.png) [@natewenger9\_171681](https://community.cartalk.com/u/natewenger9_171681)\ **Post date:** [October 19, 2020, 11:22pm UTC](https://community.cartalk.com/t/02-sensors/171374/7 "2020-10-19T23:22:47Z")
Thanks. The visual aid is really helpful. I’ll make certain tomorrow but I’m fairly certain the fuse is good. ---
**Author:** ![natewenger9\_171681](https://avatars.discourse-cdn.com/v4/letter/n/ecae2f/32.png) [@natewenger9\_171681](https://community.cartalk.com/u/natewenger9_171681)\ **Post date:** [October 20, 2020, 11:43pm UTC](https://community.cartalk.com/t/02-sensors/171374/8 "2020-10-20T23:43:18Z")
Fuses still intact.