2004 Hummer H2: OBD Code P0141?

Check Engine light code Po141.

First of all check the fuses.

In the underhood fuse panel, check the O2 A and O2 B fuses. If these fuses are both good then the problem is the heater circuit in the bank 1, sensor 2 oxygen sensor.
In this case sensor needs to be replaced. This sensor is on the drivers side, behind the catalytic converter in the exhaust pipe.

It will not harm anything. This sensor just monitors efficiency of the catalytic converter. It does not affect the way the engine runs at all. Okay to drive for a while until you are able to fix.
But dont ignore the issue.
This details will help.
Thanks.

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