I suggest you use a multimeter to check the voltage across the battery terminals. It should be around 12.4 volts. If under 12 the battery is either not being charging or is faulty.

Electrical problems, either alternator or battery, are much more common than starter problems.

 

I will do that in the morning. The battery is not too old, and the alternator was replaced, for the 3rd time, about 6 months ago. I need to drag it back to the house, then I will check the voltages. I also have a Ford Edge with push button start and when the battery is weak it will try to start and everything will dim out on it. Does the Murano not do the same thing?

 

If the battery is weak, Murano won't start at all. I got my Murano brand new. Three years later, one morning it wouldn't start and you could only hear clicking noise. My heart sank. It turned out to be a weak battery.

 

^^^This is right on target. I suggest checking the battery after it has sat overnight to see how strong the battery is. Batteries are cheaper than alternators. Also - if it turns out that you need an alternator, use ONLY a Nissan manufactured alternator. We have had tons of reports of aftermarket alternators being bad when they're installed. I usually use NAPA or other remanufactured alternators, but on a Murano I'd bite the bullet and install a Nissan OEM alternator.

Let's hope it's a battery, not the alternator. That's easier all around. Just document the conditions under which you test it, and the results. We'll help interpret them.

 

Well, the battery was low, but after trickle charging it for about 4 hours it was up to 12.53v and still nothing but what sounds like a relay click that sounds like it is from under the dash when I press the start button. As far as the alternator, I replaced it twice with reman'ed, then for the third time the parts house took pity and replaced it with a new one for me. I haven't had any trouble since then with it. I will pull the battery tomorrow and have it load tested (it is about 20 months old), but assuming that it passes a load test where should I look?

 

Use your DVOM to check for battery voltage at Terminal #80 of the IPDM (fuse box in engine compartment) while trying to start the engine. Terminal #80 (thick black wire) is the power feed to the S terminal of the starter. If you're getting power to that terminal then you're likely headed in the direction of a bad starter, but you would need to go right to it to check at the S terminal connector, make sure the B terminal has power, and do a visual inspection. You should also do voltage drop testing, especially for the ground side of the circuit.

 

OK, today it is finally warm enough to get outside and test. I DO have power at terminal 80 for about 5-8 seconds after the start button is pushed, then it goes back to zero. I assume by saying I need to go right to it you are talking about tearing to down and checking at the starter itself. If so, which is the S terminal on the starter and which is the B terminal. Should the B terminal have 12 volts as well, and when should it have it? Also, how do I do voltage drop testing? I assume you mean making sure the ground terminal has continuity to the neg side of the battery, but if not, please let me know.

Also, reading another thread I checked the voltage on terminals 30, 45, and 72. With the ACC on and the car in park I had voltage on all three, but it appears to be about .25v less than battery voltage. I don't know if that is relevant.

Thanks

 

I assume by saying I need to go right to it you are talking about tearing to down and checking at the starter itself. If so, which is the S terminal on the starter and which is the B terminal?

Should the B terminal have 12 volts as well, and when should it have it?

The B terminal supplies the power to the starter motor through the solenoid. It is hot at all times so you should be reading battery voltage even with ignition off.

how do I do voltage drop testing? I assume you mean making sure the ground terminal has continuity to the neg side of the battery, but if not, please let me know.

Voltage drop testing measures how much voltage is lost ("dropped") through the circuit before it ever reaches the component to be powered. Obviously, the lower the better or else the component will not receive the voltage necessary to operate properly, if at all. To do voltage drop testing on the starter, connect the DVOM leads to the battery positive terminal and starter B terminal to test the positive side of the starter circuit and then to the battery negative terminal and starter housing to test the negative side of the starter circuit. Tests must be done with the circuit under load (i.e. while trying to start the engine). Measurements should be less than 0.5 volts (lower is better). See also this diagram.

Also, reading another thread I checked the voltage on terminals 30, 45, and 72. With the ACC on and the car in park I had voltage on all three, but it appears to be about .25v less than battery voltage. I don't know if that is relevant.

Those voltage readings are through control modules so they will always be a bit less than what is measured right at the battery posts. Fortunately, you won't have to go through what that guy is currently going through.

 

OK, let me get it torn down so I can see the starter and I will do those checks and let you know the outcome. It may be tomorrow before I get it all apart. Thanks again for your assistance!!

 

OK, I got it all torn apart. I do have power on the B terminal. I also have battery voltage on the S terminal when I hit the start button, although I had to unplug it from the starter to read the voltage on it. As for the drop test, the meter that was hooked up to the B terminal and the positive side of the battery showed 0v, the one that was hooked to the starter frame and the negative terminal showed .01v.

 

Time to buy a new starter.

 

Got a new Duralast starter put in today and it fired right up. I still think the battery is a little weak, but as long as I run it for a few minutes after starting it it will start right back up. I appreciate all your assistance! I could not have diagnosed this without your help. If you're ever in KC I owe you a beer!

 

Glad to hear you're up and running! Your case was pretty much a text book example of diagnosing a bad starter.

 

look at this you tub video

 

Well, aside from the fact that all he wants to do is ***** about Nissan, he makes one (1) decent point, which is that the fuse assembly seems to have multiple failure points which cannot be replaced as individual fuses. It might indeed make sense for the owner to carry a spare.

Why Nissan decided to pack multiple non-replaceable fuses into one unit like that makes no sense to me. Each of those fuses should be an individual unit which user-replaceable. They could have built an identically-sized plastic block with all the required mounting points for standard fuses, they just didn't bother.