Starting issues

[nsxon19s]

Okay i have 2000 q45 with 100000miles on it. The car ran fine but when it got super cold over night the next morning the battery be compltely dead. happened twice. jumped it ran good. Figuring it was battery had it tested but came back good. Drove it another week and it went dead. This time, replaced battery but now it clicks and wont start. Thinkin its starter but battery terminals i hear are problem. Can the big fuse off the positive battery line go bad? any help would be great thanks

[Q45tech]

Take to technicans for an alternator load test to measure the ampere capacity of alternator to recharge.

[qsiguy]

The fuse won't be intermittent. It's either good or bad. I'd certainly make sure your battery connections are clean and solid. When it won't start have you checked the battery voltage? If voltage is still up at the battery but still won't start then you should be looking at the cables and starter. Also, make sure you are checking the battery while someone tries to crank it. If it drops below 9-10 volts it's dead which could be a battery or the alternator. Which is what should be one of the first things you need to get tested as Tech said.

If alternator and battery test good then you need to test for engine/key off amp draw and isolate the drain.

[goody90q45]

Thinkin its starter but battery terminals i hear are problem.

Definately follow Tech's advice and have the alternator tested. Autozone and a lot of other parts stores (my local Napa) will check it for free. A bad alternator kills a battery and vice versa. Sort of a lose-lose situation if you let problems with either go on for too long.

Since you mentioned battery terminals (clamps) take a close look at those connections also. The clamps wear out, holes in the connectors corrode, and before you know it the clamp doesn't tighten enough to get a good enough connection to engage the starter but everything else in the passenger compartment works. I speak from experience having replaced my starter after hearing the "click, click" when the only problem was a marginal positive terminal.