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41

Rule(s) of thumb: Drive the car once a week, long enough to get the engine to normal operating temperature. Change the oil every 3,000 miles, or since you are not driving much, every 3 months. If your car stays stationary for very long times you need to be concerned about dry rot or the rubber on the tires, but if you follow #1, you won't need to worry ...


32

Preform open circuit voltage test. Vehicle off, battery disconnected, check the voltage with a DVOM (Digital Volt Ohm Meter) 12.66 = 100% state of charge 12.45 = 75% state of charge 12.24 = 50% state of charge 12.06 = 25% state of charge 11.89 = 0% state of charge 10.45 - 10.65 = bad cell, battery should be replaced If the battery is at or near 100% then ...


31

According to 2010 Prius Emergency Response Guide (page 10): Being electronic, the gearshift selector and the park systems depend on the low voltage 12 Volt auxiliary battery for power. If the 12 Volt auxiliary battery is discharged or disconnected, the vehicle cannot be started and cannot be shifted out of park. The auxiliary battery is located in the ...


31

From an electrical perspective, it doesn't matter. However, a lead-acid battery that is charging or discharging rapidly will give off hydrogen, which is highly explosive. Since you generally make the ground connection last, there's a good chance that you'll get a spark, which is enough to ignite the hydrogen. So while it's unlikely that you'll have ...


25

This is going to get a bit technical but should still be understandable even if you slept through chemistry classes. When is hydrogen dangerous? Just as with the fuel-air mixture in an engine, hydrogen is combustible only when it's within a range of concentrations. We use what are called the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) ...


24

In most cases, the stock-size battery is correct, and that's what you should stick with. A smaller battery is likely to fail you sooner, unless you live somewhere without a winter (Hilo?). A larger battery is an extra expense, extra toxins, extra weight, and won't give you dramatically longer life. CCA (cold cranking amps) is the main thing to pay ...


19

The battery is toast. Save yourself potential serious injury. Buy a new one. If the battery has been dead for eight months...it is pretty much a goner.


17

Use the jumper battery to start the engine, then disconnect it and leave the engine running (with no current drain such as lights, heater fan, radio, etc). The car should charge its own battery to 80% charge in about two hours (assuming the battery and alternator are in good condition; the battery may be damaged by being uncharged for so long, but I've never ...


16

Standard digital multimeters can measure current and help you identify what in your vehicle is consuming your battery's juice. Get an electrical diagram of your vehicle and try to narrow it down by doing current measurements in the various major paths of flow. When your car is off, no (or only trace) current should be flowing. Every time the path of ...


16

The reason I would connect the positive cable first (in a negatively-earthed car) is that while tightening the positive connector with a spanner (wrench), if I were to touch the body of the car with the spanner at the same time, nothing would happen and I would be OK. However if the negative was already connected to the battery and I shorted the positive to ...


14

Your battery was dead. In many cars, when the battery can't provide enough cranking amps, you will hear a clicking instead of the normal starting sound. The starter battery draws a lot of current. When that happens, the voltage available to the rest of the system drops dramatically, especially if the battery is weak. That's why your clock reset itself. ...


14

Sure you could put a bigger battery in .What may happen is that the total proposed draw is too much for the dynamo and it will go flat.Even if it does not go flat because your appliance usage patterns are intermittent you will get a lower battery life because of the constant cycling .If dealing with the charging system is too hard or too expensive then ...


13

Find your fuse box diagram. With everything off, pull fuses out one by one and use a multimeter on the fuse socket to measure the current drawn through that circuit. That will give you some indication as to what is causing the power drain.


13

I would imagine that this sort of technology would lead to increased wear on your starter motor, as it is being used far more than it would normally be, however I would hope that they would have anticipated this and designed the starter to be more robust than a traditional one. The battery should be able to cope with it fine all the time it is in good ...


13

Chris makes a very good point regarding the hydrogen given off by the battery. There's also another reason, especially on older cars. Ground straps to the engine on most cars are notorious for corroding, so by hooking up the negative terminal to the engine you'll increase your chance of getting the maximum current flow when you're trying to crank the engine.


13

You don't need to solder them, clean the terminals really well and apply some dielctric grease or buy some battery terminal protector, this is a spray that you can spray on the terminals and this will keep the battery form corroding. I personally use heavy duty bearing grease to apply over and around the terminals, this helps really well keeping the ...


13

Your question is difficult to answer without you knowing the inner workings of an alternator. The basics. If you move a magnetic field near a coil of wire the electrons in the wire get exited and electricity will be made. The amount of electricity made depends on the size of the magnetic field and its speed. The bigger the field and the faster it's moving ...


12

A trickle charger is a good idea. It maintains the battery so it doesn't go through large charge/discharge cycles, which damages the battery. Also change the oil at six months whether the mileage is over your limit or not.


12

Most modern diesel engines (ie: engines after mid-80s) require some electricity to run because they are electronically controlled. This is due to computers controlling the fuel charge and monitoring of the engine itself. Without this, the diesel engine has no control. They also require electricity to power the primary fuel pump, to move the fuel from the ...


12

Corrosion on the terminals is due to hydrogen gas being released from the acid in the battery. It mixes with other things in the atmosphere under the hood and produces the corrosion you see on the terminals. Generally, if the corrosion is occurring on the negative terminal, your system is probably undercharging. If on the positive side, it is probably ...


12

This step is a carryover from days gone by and is not needed in modern vehicles. Batteries from 50 or 60+ years ago were not as powerful or reliable as modern ones. Older batteries had difficulty handling the load of the starter motor alone. Engines cranked longer before starting and were cranking large displacement engines. Any added load from wiper, radio ...


12

tl dr: Corrosion (once cleaned) is not a huge issue. It is just typical corrosion on the battery terminal. See this image: (NOTE: This is a 6V battery, but the same principles apply.) The blueish color you see is hydrated copper sulfate. When acid vapors escape from the battery, it can cause a reaction with any copper which may be in the terminal. The ...


12

Lead acid type batteries, such as this, like to be charged very slowly. Under 5 amps for many hours would be best. During fast charging the internals overheat and electrolyte can boil. Best to charge slowly if time allows. This type battery has its worst damage happen when it is stored discharged. The chemistry in this state is more acidic. This acid ...


12

I can't give you numbers or calculations without some work, but I can tell you than energy is never free. Cars have an A/C compressor that is mechanically driven by the engine because this is the easiest way to get the job done in a typical consumer car. An A/C compressor actually takes a huge amount of energy to operate. In fact a central A/C unit for a ...


11

Air Conditioners are run by a belt that is connected to the crankshaft. The engine turning causes the A/C Compressor to move. When your A/C is not turned on, a clutch disengages the A/C Compressor's internals from the pulley on the belt. This allows that belt to free spin, not adding load onto the engine. When the A/C is turned on, that clutch is engaged ...


11

Why and when would one use such charger? To my mind, the major needs fall into two major categories: You have a vehicle that does not get driven enough to keep the battery up to charge against its passive drain. Common examples would include the summer-only car or the utility vehicle that you only use for heavy hauling. In either of those cases, I ...


11

Yes it can be easily done, but based on your scenario it's not necessary unless you want to sit for extended periods without running the engine. If you are going to leave the vehicle running for Air Conditioning for instance then you don't need to do anything it should work fine as equipped from the factory. Here are some things to consider If you still ...


11

The battery is bad. You need to get a replacement ... the one you bought may still be under warranty, though probably pro-rated at this point. More than likely, your current battery has a bad cell in it which doesn't accept the charge it is supposed to. Since batteries are built with multiple cells configured to work in series, one cell is all it takes to ...


11

I am no expert in this topic, but I don't think a "cloud of gas" forms around the battery. Hydrogen gas is the lightest gas of them all (0.089 g/l) and won't pool up if leaked. It will simply rise as long as the bonnet is open because it is less dense than air, which is mostly much heavier nitrogen (1.25 g/l) and oxygen (1.4285 g/l). My guess is that the ...



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