# Code P0340 After Alternator Replacement



## geoffrowens (Dec 21, 2011)

My girls 96 Altima was dying on her while driving home. We'd jump it and it would run for 2 minutes and fade out and die. So i assumed either the battery or alternator were bad.

We left it on the side of the road and pulled the battery from the car. Took it to the Autozone and had them charge it and test it. The battery isnt that old and took a charge just fine and came back 100%. I put the battery back in the car and started it up. While i was driving it straight to Autozone to have them test the alternator i noticed that the Airbag, battery, brake and check engine lights were on. 

They tested the alternator and it failed. Luckily it was under warrenty so i got the replacement one and put it on. Car fired up and drove fine. The batter and brake lights were out. I manually cleared the airbag light and its stayed off. The Check Engine light was still on so Autozone scanned it and came back P0340 (cam sensor fault). I had them clear the code since thecar was driving fine. The light stayed off for about a day and has come back on with the same code. 

I dont believe that the cam sensor is bad since the check engine light came on after we disconnected the battery. Ive read that alot of times this code comes up when electrical components are messed with. The battery is good and the alternator is brand new and working properly. Any ideas what might be causing this? Is there a better way to reset the ECU and "completely" clear the codes.


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## altimanum1 (Jun 19, 2009)

Have you try checking the connector/plug of the sensor. Also i know that sometimes that code comes up when you have low battery voltage.

I own a 96 altima myself an my alternator has messed up 3 times on me an i had to replaced the battery 4 times, but it was because i had a short on the fuse box. But I had never had that code.

When your alternator went out and didnt charge youre battery might have messed up youre sensor. You should try replacing it, or before you do you should check youre charging system with a multimeter to check its working properly. you might have a short which trigger the obd code.

I found the problem on my car using the multimeter i realized that when i turn my car on it was reading 16v to the battery which kept messing it up.

Also does youre car run ok? Or does it stall?


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