Need car problem diagnoses

[BP]

Yes, and pull the ground off the battery while it's running. If it remains running then the alt is doing its job.
Just my 2¢. I'm no mechanic but that's what I'd do.

That's probably the worst advice you could give someone with a car built in the last 25 or so years. It's so bad that Nissan even has a TSB telling you not to do it.

http://www.370zcoupe.com/TSB/1SE40.pdf

On an 09 Maxima it could easily destroy the transmission controller ($1200+) as well as the ECM and BCM. You could easily destroy $5k worth of parts by disconnecting the battery with the engine running.

I'd check the battery voltage before starting and then if it starts check it again when running. If the voltage is below specs it could be an alternator. If it's anything beyond that I'd strongly suggest taking it to a Nissan dealership. This is a very complicated car and parts are very expensive. This could be as simple as a battery/alternator issue or it could be something with the IPDM.

Also note that when you disconnect the battery there are a few things that need to be reset with a scanner depending on the car's options. The steering angle sensor, power windows, sunroof, automatic seats and HVAC system may need to be programmed to work properly.

[lowthreeohz]

Lol @ moltimeter, you gonna measure the resistance of a snake skin?

[yellowstang]

Charge it, wait till dark an lay the rear seats down so u can see if the trunk light is on or not

Or, charge it and close the garage door so the garage is dark, and chk the trunk light, visor light.

[JimD]

That's probably the worst advice you could give someone with a car built in the last 25 or so years. It's so bad that Nissan even has a TSB telling you not to do it.

http://www.370zcoupe.com/TSB/1SE40.pdf

On an 09 Maxima it could easily destroy the transmission controller ($1200+) as well as the ECM and BCM. You could easily destroy $5k worth of parts by disconnecting the battery with the engine running.

I'd check the battery voltage before starting and then if it starts check it again when running. If the voltage is below specs it could be an alternator. If it's anything beyond that I'd strongly suggest taking it to a Nissan dealership. This is a very complicated car and parts are very expensive. This could be as simple as a battery/alternator issue or it could be something with the IPDM.

Also note that when you disconnect the battery there are a few things that need to be reset with a scanner depending on the car's options. The steering angle sensor, power windows, sunroof, automatic seats and HVAC system may need to be programmed to work properly.

Totally agree, do not just pull the cable, if you don't have proper test equipment, don't fuck with it.

[EW]

Buy a $30 meter and get after it.

[houstondallas]

Just tried jumping the car off and it still wouldnt start. It was popping like it was trying to start and the electrical would try to come on but it wouldnt turn over.

What does that mean now? Starter?

Anyone have a mobile mechanic who can come fix this thing since its in my driveway?

[dcs13]

You say "popping". Not exactly a car term. Is the motor turning over and just not starting or does the starter just make a "clicking sound" ?

[houstondallas]

You say "popping". Not exactly a car term. Is the motor turning over and just not starting or does the starter just make a "clicking sound" ?

Sorry its hard to describe. Clicking is more like it. Electrical is trying to come on the car and its just clicking trying to turn over. Very similar to a dead battery but we had the cables hooked up for a few minutes and it never got past doing that. I figured if it was that close to turning over, a minute of charging from another car would do the trick

[soap]

Do Not disconnet the battery with the car running.

This. You can get away with it on old cars. But newer cars with PCM you risk sending a power surge.

[JimD]

Sorry its hard to describe. Clicking is more like it. Electrical is trying to come on the car and its just clicking trying to turn over. Very similar to a dead battery but we had the cables hooked up for a few minutes and it never got past doing that. I figured if it was that close to turning over, a minute of charging from another car would do the trick

I'd be checking connections and block ground.

[kingjason]

Put a simple 12v meter on the battery terminals. It should read in the high 12's or something like that. Have a friend, wife, or whatever try to start the car and watch the voltmeter. If it drops way into the single digits, your battery is fried. That's the only really good way to check a battery. I have seen many a parts store say a battery is ok when it was toast. I have also seen times when a plate goes bad in the battery that you can not even jump the car off or put any charge on it.

Also do you have interior lights functioning? Bad battery and they will dim out fairly well when trying to start it. If they are not dimming it may be a bad ground as stated above or hot wire. The sound you here probably sounds like a mechanical clicking noise which is the starter not having enough juice to engage. If you do have a short and drained your battery down to low, sometimes they don't recover.

[samuel642000]

Totally agree, do not just pull the cable, if you don't have proper test equipment, don't fuck with it.

This. You can get away with it on old cars. But newer cars with PCM you risk sending a power surge.

Hmm learn something new every day, been doing it this way for a long time. Doesn't help I learned on older cars.

[BP]

Hmm learn something new every day, been doing it this way for a long time. Doesn't help I learned on older cars.

It's a bad idea on anything with any kind of electronics. If you are working on something with a carburetor and points it's fine but with EFI and an ignition module you'll likely cause some damage. You can get a pretty big voltage spike that has to go somewhere and without a battery it'll blow out capacitors on the various electronics.

You also shouldn't be using an old school test light on modern cars. That bulb and it's harness can draw 10x the voltage and amperage that a lot of circuits are designed to work with.

[shumpertdavid]

Totally agree, do not just pull the cable, if you don't have proper test equipment, don't fuck with it.

Best Advice Ever

And as far as a checking for a battery drain, most all newer cars (pretty well anything injected or built in the last 20 years) have modules / computers that stay awake for 10minutes to a couple hours. Meaning they have some kind of parasitic drain until the module goes into a sleep state. This mean you may show initially you have a drain that is supposed to be there. The body control stuff generally takes up to 30 minutes to go to sleep. Any using a test light to check for this isn't very accurate, however if it would kill a battery in a day then it's pretty good sized.


And as stated above, get a simple volt meter and see what battery voltage is. Your descriptions are too vague to give anything remotely accurate.

[lilvega]

I had a Nissan/Datsun 280z years ago that did the same thing. Every other day the battery was dead. No voltage draw that I could find so one day I just sat by the cat for a while. After about 30 mins or so I hear the fuel pump come on and it ran for at least 30 mins then shut off. A few mins later it came on again. Did this over and over. The fuel pump relay was going bad.