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i was driving down the road and the car just turned i made it about a block away from my house. I waited there for about 5 minutes and then i tried to turn it on and it worked, but about a week later it happened again and I was stuck in the exact same point. however this time it didn't want to turn on so i towed it back. The electrical part worked fine, headlight, radio, dash, etc.. But it wouldn't crank it would just be one single click the battery had around 12v and i checked all the fuses and they were fine as well. About a week later the electrical wouldn't work, no lights, nothing, and theres no click when you turn the key anymore, the battery is pretty much almost dead now. I'm highly suspecting it to be the alternator and definitely replacing the battery but I just want to get someone else's opinion about it or someone with a similar experience.
 

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i was driving down the road and the car just turned i made it about a block away from my house. I waited there for about 5 minutes and then i tried to turn it on and it worked, but about a week later it happened again and I was stuck in the exact same point. however this time it didn't want to turn on so i towed it back. The electrical part worked fine, headlight, radio, dash, etc.. But it wouldn't crank it would just be one single click the battery had around 12v and i checked all the fuses and they were fine as well. About a week later the electrical wouldn't work, no lights, nothing, and theres no click when you turn the key anymore, the battery is pretty much almost dead now. I'm highly suspecting it to be the alternator and definitely replacing the battery but I just want to get someone else's opinion about it or someone with a similar experience.
It well could be a bad alternator.
A properly working charging system puts out about 13.2 to 15.0 volts, but this is a general spec, and the factory service manual should be referenced for the correct charging system voltage specifications for a particular vehicle. A battery should have a static charge of 12.2-12.6 volts. If a battery is not good, the charging system may not be able to charge properly. If a vehicle is not charging properly and the battery is good, the first thing to do is to turn the ignition switch to the "ON" position without starting the engine and make sure the charging system warning light is operating. If the bulb is burnt out, the charging system will not charge. If the bulb is OK but still does not illuminate, the circuit must be tested. If the warning lamp does illuminate, then the next thing to check is to make sure the circuit between the battery positive post (+), or fusible link, to the connection in back of the alternator is good. On Nissans, this will be a thick (approx. 10 gauge) white wire to the "BAT" post on the back of the alternator. With the negative cable (-) disconnected from the battery, measure the resistance between the "BAT" post on the back of the alternator and the battery positive (+) post; the resistance should not be greater then 0.2 Ohms. It's not uncommon for this wire to get corroded and burn up, creating resistance in the circuit. So, before assuming an alternator is bad, make sure this circuit is good and battery voltage is getting to the alternator. It's also important to make sure the alternator belt is tight and not slipping and the battery connections are clean and tight.

Assuming the charging system voltage is ok and the battery is good, the next thing to do would be to have a parasitic draw test performed; there should not be more than a 50 milliamp draw on the system with the ignition switch in the "OFF" position. If there is a higher draw, you need to do some testing to find out where the draw is coming from. Remove fuses one at a time until the draw goes away or falls into acceptable range.

The later-model cars have adopted what Nissan calls “power generation voltage variable controls.” This system monitors battery current and varies voltage to the regulator, reducing the load on the engine and resulting in better gas mileage. By varying the voltage to the alternator, engine load due to power generation of the alternator is reduced and fuel consumption is decreased. The battery current sensor is installed on the battery cable at the negative terminal. The battery current sensor detects the charging/discharging current of the battery and sends a voltage signal to the ECM according to the current value detected.

Also, it is NOT a good idea to disconnect a battery cable on a computer controlled vehicle while running to test the alternator. This is a good way to damage an ECM. When a charging system is not charging, or overcharging, a lot of "strange" things can occur. It's not uncommon to see a multiple of stored trouble codes in the ECM memory. So, whenever a car is setting a multiple of trouble codes, idling funny or stalling, or anything out of the "norm," test the charging system before you start pulling hairs!

When replacing electrical components such as alternators, starters and distributors, fuel injectors and sensors, always replace with new or reman'd Nissan OEM components; aftermarket components generally don't last long, don't work right and many times are DOA.
 
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