Why do you have to change a car's alternator when changing the battery?
Well, three possibilities here.One. You alternator failed, killing the battery. Replace the battery, test the alternator. You can't test an alternator with a failed battery. Start the car with the new battery, voltage should go up from 12.5ish to 13–14 volt range.Rev the engine slightly (2500–3000 rpm). Turn on all the electricals, lights, air conditioning, etc. If the voltage drops below 12.8 for more than a second, look at replacing the alternator. It should spring back to 13ish.Often alternators will have a modular regulator. Most parts shops can test and determine if the alternator itself is blown, or if it's just the regulator. The brushes may be gone, and are sometimes integral to the regulator. Either way, it's cheaper than a full alternator.If the alternator is bad — doesn't make voltage; or is weak — doesn't hold voltage: then fix or replace it with the battery.Check the feed cables and battery connections on the off chance they're bad. You should do this regardless.Two. This is a low probability. Your battery failed, killing the alternator. This can happen in the case I forget a dead short in one of the cells of the battery, or a near total loss of liquid in your battery. Either way the battery case will likely be distorted, or even cracked. It will have a voltage less than 9. It may even stink of rotten eggs, with a slight taste of chewing on foil.Three. Your mechanic is a liar and a thief who's trying to get more money out of your pocket and into his. If he says that you have to replace the alternator because the battery is bad, this is the case.
Why won't my car start even after I put a new battery in?
Before retiring, I owned an auto repair shop. A guy comes in and says he replaced his battery, replaced the starter twice and the car would still not start. He bought a “rebuilt” alternator and wanted us to install it for him. I told him if he had a new starter and battery, there was no likelihood the alternator was involved, would he like us to troubleshoot the car and try to find the cause of the problem.He aid all he wanted was for us to install the alternator, nothing else. I wrote up the repair order Car does not start, customer wands us to install his supplied alternator and will not allow us to diagnose the problem or touch anything else. Under that circumstance, we are to push the car into the shop, install his supplied alternator and push the car out. Under no circumstance are we to attempt to start the car. The labor will be paid for in cash before the car is pushed out of the shop, the customer will wait for it.I had the customer sign the order and the instructions, and did as he asked.He paid and we pushed the car out of the shop. He tried to start it, nothing happened ao he came back into the shop mad! I told him to read what he had ordered us to do, and then, would he allow us to diagnose the problem and make a repair, charging clock time and allowing us a half hour diagnostic time, to try to find and fix the problem. He agreed and signed a repair order. The Mechanic went to the parts department, got and installed a new ground cable. The problem was that the owner had replaced the ground cable with a short one that he bolted to a loose bracket on the right side of the engine. There was nothing wrong with his battery, starter(s) or alternator. The classic DO IT TO YOUR SELFER.
Mechanic said battery isn't strong enough for car?
A 15 second battery load test will tell you the reserve amperage capacity, Amps. spin starter motors not volts. A battery can "appear" to be fully charged @ 12.6 volts yet have little or no reserve amperage. If the battery DOES check out OK a trusted private mechanic should do a starter amp-draw test on your discontinued Ford engine - starter From now on, the best measure of a batteries amperage capacity is the MOST Cold Cranking Amps @ 0 degrees Fahrenheit and the longest free replacement warranty which will fit in your battery box.
Alternator overcharging battery?
Why is it over charging? Well gee don't have any ASE certificates hanging on the wall, in fact I don't even work on Passenger cars or trucks, but here's why its over charging, Your alternator being called an alternator because it generates alternating current, as in AC voltage, in your case about 60 volts, whereas it is routed through what is commonly known as a voltage regulator, which in fact is incorrect nomenclature, as that's a throw back from the days of old when the Generator was used which generated DC voltage, the regulator regulated the amount of DC voltage due to RPM to the battery, somehow the name stuck, what you now have is actually a Rectifier which changes the AC voltage to DC voltage, rectifying the problem so to say, the most common is the Zener Diode Tree, basically its a series of diodes and resistors in some cases, or the Avalanche Diode Tree, which is basically the same thing but different, and I will not bore you with the details, somewhere in this circuit a diode has failed allowing to much DC voltage to pass, the rectifier is still changing the AC to DC but its not cutting it down enough, remember your still working with 60 volts AC, normally you see a total failure and the Alternator and rectifier fail to put out anything, except maybe about 5 volts AC, its a fail safe built into the diode tree, So that's why, and yes I do have many certifications, just not in the automotive field, think much bigger more complex multimillion dollar machines,
Changed Car battery but now its making a weird sound?
So my car battery died recently and I got a new one and put it in, I tried starting it and it was cranking just not starting up, all the lights work and the radio comes on, so I tried to tighten up the terminal clamps, and given it another start but now it's making this horrible noise when trying to start, like a constant loud clicking, like it's trying to crank normally but it just sounds horrible, could it be corrosion on the connection to the battery? The lights and radio still work when I turn the key just to start them but as soon as I try to start the car the sound starts and it sound like crap.
HOOKED UP CAR BATTERY WRONG..NOW IM F**KED!?
its a lexus es300 1994 i connected the battery back words and put the negative on the positive And the positive to the negative.. with sent out a little spark.. now this mechanic is saying i messed up the whole computer of the car.. i would understand if i blew a fuse, or the alternator, or tosted some cables.. but the whole cpu??? that doesnt sound right.. he changed some fuses and now the power comes on.. and the engine chokes like it wants to start but it doesnt .. i dont under stand, any advice?
Hooked up battery backwards now car pops when starting but wont turn over?
I know I did a dumb thing. I changed the battery in our 2007 mazda 5. i put it in backwards and when I connected the terminals it started sparking. It was connected for about 5 seconds. I changed it around and hooked it back up. Now when I go to start it there is a Peiping noise like the starter is kicking out but there is no crank or sign of it wanting to turn over just a pop. All the lights and instrument panel work. I was told it could be the main fuse but looked on line and in the manual and can not find where it is located or what it looks like. Can anyone give me some ideas? Please refrain from the smart *** comments as I all ready got enough from my wife.
Why does my car run different after changing the battery?
I recently changed the battery on my 2002 ford focus and now it runs different. Well, it still feels smooth and sounds fine but the rpm will go all the way to 3,000 before it changes to second and third gear. It also makes a hard change of gears or however you say it. Whenever I change gears it feels hard on the car. What do you think it is? It used to change gears very smoothly before I changed the battery.
Why does my car battery mark half full when I just installed a brand new silver dura last?
Could it be that my truck is not reading it right? The battery is brand new and tested.. At the beginning the mechanic said it wasn't the alternator, starter, sparks, compressor, so I changed the battery. My truck turns on normally now but the pointer inside is pointing right at the middle so indicating that the brand new battery is is not fully charged or something. Anyone know what the case is? Ford f-150 year 2000 5.4