I have a 97 SLS and decided to install a new battery. OOPS!! I guess I should have used a jumper and connected another battery to the cig lighter to maintain memory. Well, I DIDNT. Now, I have about 5 codes in history, and a current code of P1139 which isheated 02 sensor insufficiant switching bank 1 sensor 2".

Now, can anyone, first of all, help me clear all the codes, and then tell me what I need to do to remedy this 02 sensor thing?? I would really appreciate it since this is my only daily vehicle at the moment. Thanx in advance.

You normally don't have to rig a new battery to "maintain memory"; the codes were probably not caused by changing the battery.

Your car has 4 O2 sensors. 3 are fairly easy to change, one is a little harder. They are located one in each exhaust manifold, then one ahead of and one behind the catalytic converter. They are regular maintenance items at 60-75k miles.

You normally don't have to rig a new battery to "maintain memory"; the codes were probably not caused by changing the battery.

Your car has 4 O2 sensors. 3 are fairly easy to change, one is a little harder. They are located one in each exhaust manifold, then one ahead of and one behind the catalytic converter. They are regular maintenance items at 60-75k miles.


Well, I only have 30K on it, but the check engine light went out. All the codes are now history. I dont know what the hell happened but everything is good. Guess I'll have a spare 02 sensor on my hands since i already ordered it. Is there any easy way to clear out history codes?

You can use the onboard diagnostics to clear codes, but there is really no need to clear history codes. Most errors auto-clear after a set number of successful cycles.