Alternators

It depends on which diode, but sometimes it can.

This sounds similar to a problem I had once. In the end, replacing the battery cables solved the problem. If yours are old and you live in a climate where they're exposed to salt, humidity, or other corrosion, I'd start by replacing both battery cables. Or, if there doesn't appear to be any corrosion probability of bad cables themselves, try removing the cables from the battery, clean the terminals very well, reinstall them tightly and coat them with grease to prevent corrosion at the battery posts. You should probably also check the cleanliness and tightness of the connection where the Negative (-) cable bolts onto the car's frame (usually on the same side as the battery, just below the engine). Remove the screw, clean everything to bare metal, reinstall and tighten. Then cover with fresh grease (or vaseline will work - or spend a few bucks and buy battery terminal protectant spray).

Should give more info. Did they come on at the same time or days apart? Could you have 2 problems not just one? If they both came on together you could have a wiring problem. If it has a sensor for the light in the master cylinder it could just be low on fluid, bad sensor or damaged wiring to sensor. Have you checked the output of the alternator with a digital multimeter? Check it at the alternator first, should be 13-14 volts while running. You can check it at the battery also, again should be 13-14 volts while running.

<p>Replacing the alternator is a challenging but straightforward exercise for the novice car mechanic. Consider also replacing the alternator belt at the same time. This should be replaced every 60,000 miles. </p>

<p>The alternator is found on the left side (as you face it from the front) of the engine, toward the front. It is a small roundish silver-colored thing that seems to have a lot of ventilation holes in it. </p>

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Start by removing the cable from the negative terminal of the battery (the one without the red plastic cover). This is always the first step when working on any part of the electrical system. Use a 10mm socket to loosen the connector, and then slip it off the top. Tuck it out of the way so that it doesn't accidentally connect again. </li><li>

Remove the cable from the alternator. The cable is attached under a "boot" attached to the top. Slip the boot back, and use a 10mm socket to remove the attaching nut. Be sure not to drop it into the engine compartment, because you will never find it. After removing the screw and detaching the cable, remove the boot as well, so it doesn't fall off and get lost. </li><li>

Remove the wire harness from the alternator. This is a small plastic connector with many wires. There is a small spring clip on the side. Squeeze it and pull firmly. Tuck all the wires out of the way. </li><li>

Identify the three bolts holding on the alternator. The "top" bolt is on the top on the left side. The "bottom" is in on the bottom, in the same orientation, but hard to see. You may need to find it by feel. Third is the "adjuster" screw, which is near the bottom bolt, but sticking straight toward you, visible. Loosen all three bolts slightly (12mm for bottom and adjuster, 14mm for top)

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Now remove the adjuster screw completely with a 12mm socket. This is like the longest screw you have ever seen, and it takes a while to get it out.

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Remove the bottom bolt with a 12mm socket. There is a small "cube" that comes out with it, be sure not to drop it.

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Remove the top bolt with a 14mm socket. It looks like a long bolt, but it is only threaded a short way, and should pull right out after a while.

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Now wiggle the alternator loose. If it is stuck, you can bang it a little with a piece of wood and a mallet.

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Slip the belt off of the pulley on the alternator. Don't try to remove the belt entirely from the engine right now.

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Now you have to extract the alternator from the engine compartment. This can be more difficult than it looks, because you have to manipulate it around some wires and hoses. Gently flex the hoses as necessary to make room, but try not to break anything. You may also want to temporarily disconnect the right headlight wires if they get in the way.

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After the alternator is removed, remove the belt by unhooking it from the lower two pulleys.

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Now take a break, clean your hands, and relax. Turn the belt inside-out and inspect it. It should be free of cracks, tears, and missing spots. Get a new one if you need to. Do a sanity check on your new alternator. Make sure the connectors are all the same, the bolt holes are in the same place, and the belt fits on the pulley. Sometimes an after-market alternator will look a little different, but it should still fit.

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Hook the belt back on the two lower pulleys.

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Manipulate the new alternator into place. The part with two bolt holes is the top, one hole is on the bottom, and the electrical connections are in the front. While you are doing this, slip the belt onto the pulley, and make sure it's still wrapped around the lower pulleys.

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Put the top bolt in. The top bolt is the long one with only a small amount of threading on the end. You will need to wiggle the alternator to get the holes lined up. Tighten the bolt just a few turns to make sure it's in all the way, but do not tighten it all the way yet.

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Look at the "cube" you removed in step 5. There are two holes; one with threads, and one without. Put the bottom bolt through the hole _without_ threads, then try to screw it into the bottom hole on the alternator. You probably have to do this by feel. There is a slot that the screw goes through before actually entering the alternator hole. Tighten this bolt most of the way, but not fully tight, so that the "cube" can spin a little in place.

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Put the adjuster screw in. This goes through a slot, and then into the other hole in the "cube". Start tightening this screw; it will take a while.

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As you are tightening the adjuster, the belt will begin to tighten up. Check it regularly, and do not overtighten. Do not overtighten! The belt should not be violin-string tight, nor should it be limp and floppy. The belt is tightened when you can push it about 1/2 inch in the middle.

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When the belt is the correct tension, tighten the top and bottom bolts on the alternator fully.

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Reconnect the wire harness (it should snap right on). Slip the boot back onto the cable and connect it to the alternator with the small nut.

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Reconnect the negative cable on the battery.

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Now its time to test your work. Make sure all tools and stuff is removed from the engine compartment.

With a multimeter, check the voltage between the battery terminals. (Set the multimeter to the VDC or _V setting. If your multimeter has several sockets, the red probe should be connected to the "V" socket, and the black probe to the "COM" socket. Clip the black probe to the negative terminal of the battery, and touch the red probe to the positive terminal, under the plastic cover.) It should read between 12 and 13 volts.

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Start the car. Make sure the alternator (battery) light on the dashboard goes off.

With the engine running, turn on the headlights and the fan. Check the voltage between the battery terminals again. It should be between 13.5 and 14.5 volts.

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Celebrate by re-programming all your radio stations.

If you replaced the alternator belt, it needs to be retensioned after running the car for 15 minutes. Stop the engine, loosen the top and bottom alternator bolts, and tighten the adjuster bolt as before. Then retighten the top and bottom bolts.

If the battery is fully charged and the starter is working properly it will turn over and start. The alternators sole purpose is to supply voltage to the vehicle and battery when the engine is running. When the engine is not running the alternator has nothing to do with starting the engine. If the alternator went bad and the battery was discharged then you will have to charge the battery before it will be able to start the engine. Do not jump start the engine with a dead battery if you can avoid it. This puts a strain on the alternator trying to recharge a dead battery and can damage the alternator, even a new one.

Turbo Alternators are used in thermal power stations because of the steam energy to mechanical energy conversion turbo alternator is more effitient

As long as the battery is fully charged it will start no matter the condition of the alternator. Eventually the battery will run down if the alternator is not keeping it charged.

honestly. Dont even attempt it, unless you have an engine hoist. Take it to a shop. its 170-220 labor. And save yourself an insane headache. I just attempted one and I've been working on cars for years..needless to say, its going elsewhere.

Either the belt is worn down, has some oil on it, or the belt is under-tensioned. If the V-Belt is glacy or cracked on the side wall, it is run down. Replace it. Else, If the belt is oily, figure out why, fix that problem, clean oil from pulleys, replace belt. Else the belt is undertensioned. If none of the above, then the belt may be the wrong dimension.

Alternators are generally not user repairable. It takes special tools and access to parts to repair. While there are repair centers, it may be cheaper to just replace it.

If you have the wrong size battery in a Cadillac with the northstar will it effect the alternator voltage?

There is a video on youtube. Just enter the question into the youtube search and you should find it.

Look at the front of the bracket underneath of you alternator, you will see a bolt that connects to the back of the pulley below the alternator itself. That will dial in/out your alternator and then you can tighten down the nut that holds the pulley in place. WHile it is true the tensioner is located on the top of the alternator with a dial type ratchet system, I have not had an 89-90 Jetta where this works. Usually you have to tension it with a bar of some sort prying against another pce of the engine.

This procedure is not very difficult. My teenage daughter has done it and I'm sure anyone with access to some basic tools can do it also. First, disconnect the positive terminal of the battery. Remove the serpentine belt. To do this, locate the belt tensioner (The tear drop looking thing just below the alternator pulley) and look for the 3/8 square hole at the bottom of the tensioner. Take a 3/8 breaker bar, or ratchet and insert it into the square hole on the tensioner. Apply pressure on your breaker bar to the left and notice the belt will loosen. Apply enough pressure until you can slide the belt off the idler pulley (located just below and to the right of the alternator). slowly release the spring tension and remove breaker bar. At this point, you should be able to remove the belt from the alternator pulley as well. At this point you can remove the wires, or if you prefer, remove the wires once the alternator is loose of it's bracket. This would give you a little more room to take loose the wires. Remove the three bolts from the alternator. One is located on the right, one on the left, and one on the top back of the alternator. The alternator should fit snug into it's bracket, so you may need to use a screwdriver to nudge it from the bracket. Remove the wires from the alternator if you have not done so already. Before heading to the parts store, rotate the idler pulley and the belt tensioner pulley to make sure that they rotate smoothly without noise. If they make noise or rotate roughly, replace them also. Take the alternator with you to the parts store to make sure you get the right one. Check that the electrical connections are the same and that they are located in the same position. I have had them off by 180 degrees at times. Make sure to keep the little electrical nuts or washers from your old alternator if the new alternator does not come with them. Make sure the pulley on the new alternator has the same number of groves as your old alternator. If needed, some parts stores will change the pulley for you if necessary. Follow the reverse procedure to install the new alternator. You just saved yourself a chunk of money

You have to release the tension bolts, and the actual bolts that hold the units on, after this make sure you have slack to remove the belts paying attention to which one came out first because that will be the last one to go back on. I would recommend replacing all the belts, the power steering can be overlooked and will start to squeak.

I recently replaced the alternator on my 96' Lumina. 1. Remove the serpentine belt off the engine by locating the belt tensioner and removing the tension req'd to remove the belt. (there is usually a diagram in the engine compt. showing the tensioner location and belt path) 2. Remove required bolts (2) I believe... & elec. harness plug from alternator. 3. Replace alternator & reverse process.

The adjuster is located underneath the alternator. Three bolts are involved, the first to loosen is the main bolt that hangs the alternator to its bracket, the second is underneath the unit on the left hand side - this would be the actual locking nut. The third is down underneath yet towards the front of the alternator; it actually moves the entire alternator forward or backward thus tightening or loosening the belt. Once the belt is tight, tighten the lock nut and then the main attaching bolt. About the lock nut, it is part of the adjuster mechanism underneath the alternator; both the lock nut and adjuster bolt are difficult to see especially if you have air conditioning like I use to.

yes but you shouldn't if alternator is not charging battery is bound to go dead and you will get stranded somewhere.

An alternator pulley transfers mechanical power from an engine crankshaft to the alternator shaft via a belt. It's interesting to note that on some engines, there are no pulleys and the power is transfered via solid gears.

The inverter isn't run off the alternator... it's run off the battery. The alternator simply recharges the battery.

Disconnect batt, disconnect wires from alt (should be 1 or 2 plug in connectors) they have a clip that locks them in, push on this with a flat blade screwdriver to release while pulling them, use a long handle socket wrench with socket that fits the pulley bolt on your tensioner. (Look for a little bracket with a small smooth pulley and spring) affix to bolt on pulley and turn against spring tension. At the same time, have a helper slip the belt off topmost accessory. Reverse procedure when done.

Drive the car to you local auto parts store and have then check the charging system.

Assuming you mean not start. The starter motor or its wiring could be dead/faulty.

Assuming the battery always ends up flat, a power leak somewhere.. ie something is being left on or shorting. Remove the fuses one by one till you notice a spark at the fuse, clocks will give a tiny spark a larger spark is what you are looking for. That circuit is draining power. Using an amp meter instead of the each fuse would be the best way of course.

It could also be bad alternator wiring.