2002 Chevy Suburban. Died on freeway. Flashes the battery light. So i changed the alternator and the battery and the car wont turn

Suburban literally died and lost power came to a slow hault. I wanted to avoid spending a bunch of money i dont have. Changed the battery and the alternator. Still wont turn over. Lights turn on. Fan starts to go but wont kick on.

My car has 114000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
It sounds like you may have a failing alternator. As you may know, the alternator charges the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator pulley. The voltage regulator is a unit that regulates the charging of the battery by the alternator and maintaining a certain amperage while the engine runs. When the alternator is not working properly, this may result in the battery quickly losing charge and the car losing all power. You may also notice a whining sound as a result of the bearings inside the alternator begin to fail. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.

How to Identify and Fix Common car Problems ?

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It is possible that the problems that you have been experiencing with the bad alternators have damaged the battery causing it to be weak. This would make the Battery Light come on. It is also possible that there is a problem with the fusible link or the alternator fuse for the charging system.
Silverado`s and Sierra`s, and pretty much most vehicles, will all have two fuse boxes. One will be located inside of the engine bay, and the second will be located in the driver side footwell.
One of the most common reasons the battery light comes on and the car battery stops charging is because of corrosion. Whether the corrosion is on the battery cables or cable terminals, it is still a problem that needs to be addressed. Another common culprit for the battery not charging is a problem with the alternator.
A dying battery can be one cause for your dashboard lights flickering. The battery plays a key role in powering your car`s electrical system. If the battery isn`t working properly, it could cause the dash lights to flicker.
A bad battery won`t usually harm your starter or alternator, however, since both of those components get their voltage directly from the battery, if the battery is underperforming, both the alternator`s and starter`s performance will be affected as well.
But when someone mentions the “alternator fuse”, they`re generally referring to the primary, high-amperage fuse (or fusible link) between the alternator and the battery. Like any fuse, the primary alternator fuse acts as a circuit protection device.
While the size of your fuse depends on the amperage of your alternator, you should generally select a fuse that can handle more amperage than your alternator is able to output. For example, if your alternator outputs 200 amps, you should choose a fuse that`s no less than 200 amps.
The cause of this problem is usually one of 3 things – a failed starter motor, a bad connection between the battery and starter motor, or a blown fuse (if present) in line between the starter and the battery.
If your car won`t start but the battery is good, the most common cause is a faulty starter – though it could also be to do with your fuel. You may have insufficient fuel to get the car going.
If the red battery light on your car`s dashboard starts blinking, then take it as a sign that your battery or charging system is not functioning properly. The battery warning light is in the shape of a battery symbol, usually with a plus and minus sign.
Regardless of what symptoms you`re noticing, the battery light is telling you a simple truth: you have battery problems, and your car isn`t getting enough current from the battery to operate correctly. That means it`s time to take action, starting with some simple maintenance.
One of the most common causes of headlight flickering is a dying battery. Your headlights rely on power from the battery to function properly. If the battery is failing, flickering, or dimming headlights may be the result.
A defective alternator can kill a battery if bad diodes or an internal voltage regulator prevents it from charging the battery. Or a diode can leak, allowing current to flow after the vehicle engine is shut off. A worn or loose drive belt, or a weak belt tensioner, will also interfere with charging.
What happens when alternator stops working while driving? The car tends to slowly lose power if the alternator has gone bad while the car is being driven. You`ll notice the headlights start to dim shortly before the car loses power and dies.
The red battery light could indicate a problem with the alternator, battery or other parts of the electrical and charging system in the car. It could be a minor problem such as a malfunction rectifier unit, blown fuse or cabling short circuit.
Apart from these seven common causes, there can be other reasons why your dashboard warning light or charging system light is on, like a: Blown fuse causing a short in your vehicle`s electrical system. Malfunctioning voltage regulator. Damaged alternator pulley.
One of the most common problems you`re likely to experience with an alternator is a failure in the bearings. There are needle bearings in the alternator that allow the rotor to freely spin inside the housing, and those bearings can break down over time as a result of exposure to heat and dirt.
While a car alternator usually lasts the car`s lifetime, it can deteriorate and malfunction under certain circumstances. Factors such as normal wear and tear, damaged parts, exposure to water or heat, and overuse can cause your alternator to stop working.
A broken fuse won`t allow current to pass. This will create a potential difference across the terminals of the fuse. At one terminal, battery voltage is present and at the other terminal, no voltage is read.
Alternator ratings range from about 60 or 70 amps up to 150 amps or more on many late-model vehicles. Some high-output alternators can generate upward of 200 amps.
Fuses often aren`t sized properly. Thus, a 30-amp fuse will fit into the same space as a 15-amp fuse. The whole purpose for any protection is to protect from having a fire.
The most likely issue is that a component is clogged. A clogged fuel filter is the most common reason, although a loss of power in your car could also indicate problems with the fuel pump or fuel line. Impurities or debris may be blocking the system, which causes the loss of power in a car.
However, you may not be able to start your vehicle after it`s powered off. But if the alternator isn`t functioning properly and the battery dies, your car may eventually lose power and stall or completely shut off.
If your vehicle won`t start, it`s usually caused by a dying or dead battery, loose or corroded connection cables, a bad alternator or an issue with the starter. It can be hard to determine if you`re dealing with a battery or an alternator problem. Here`s how to know which one is the culprit.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

2002 Chevy Suburban. Died on freeway. Flashes the battery light. So i changed the alternator and the battery and the car wont turn
ANSWER : It sounds like you may have a failing alternator. As you may know, the alternator charges the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator pulley. The voltage regulator is a unit that regulates the charging of the battery by the alternator and maintaining a certain amperage while the engine runs. When the alternator is not working properly, this may result in the battery quickly losing charge and the car losing all power. You may also notice a whining sound as a result of the bearings inside the alternator begin to fail. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

Car died while driving so I replaced the alternator and battery and car won’t attempt to turn over. What else could it be?
ANSWER : The initial failure was likely caused by a sudden fuel system (e.g., failed fuel pump) or electrical (including ignition) faiure. Prior to performing diagnostics be sure you have a fully charged battery that passes a load test. Then, confirm that the engine immobilizer system (security system) is not activated thus preventing the car from starting. If the starter motor is not functioning, check for power to the starter motor when the key is held in the "start" position. If there a large voltage drop at the starter motor or no power at all, you may have a faulty ignition switch but you do have to check out the entire starter circuit, which includes grounds, wiring (some of which is very heavy cabling), fuses, relays, the ignition switch and terminations. On the other hand, if the starter motor is getting power but the starter doesn’t work, then the starter is condemned and replaced. If you desire that a certified mechanic resolve this, please simply request a no start diagnostic and the responding certified mechanic will get the problem diagnosed and repaired for you. Please let us know if you have further concerns or questions as we are always here to help you.

Battery light turned on, car started running weirdly and it essentially died. Was able to jumpstart briefly, but it died again
ANSWER : This is likely a charging system problem (i.e. alternator or voltage regulator). As you may know, the alternator is responsible for charging the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the alternator is working properly, it charges the battery as the runs maintaining a certain amperage. When the alternator is not working properly, this may cause it not to charge the battery resulting in a very quick discharge of the battery which will ultimately lead to the car shutting down and losing all power as you have experienced. I would recommend having an expert from YourMechanic come to your location to take a look at your charging system.

Battery and oil light come on when trying to start car, take keys out try again car starts no problem and lights go away
ANSWER : Of course, don’t switch gears without being fully stopped, unless your Owner’s Manual or the manufacturer has alternative advice. However, the gear shift issue has no relation to the no-start problem you are describing. Inasmuch as you only have 6,000 miles on the car, the "constant on and off" that you believe has occurred is meaningless in comparison to the expected total vehicle service life. That is, assume what you perceive as "constant on and off", during merely 6,000 miles, might be equivalent to using the car "normally" for three years. A new car should be trouble free for at least 5 years, unless there is a defect, so your "constant on and off" is not a causal factor for any fault on the vehicle. What you might have is a defect in the ignition switch, or perhaps the immobilizer system, but if the problem is not in the switch itself, clearly there is an electrical problem.

If your vehicle is under warranty, by law the dealer MUST repair the issue you are describing within a prescribed time frame and number of "attempts", otherwise the dealer will run afoul of Federal and state Lemon Laws that give you very specific rights, and recourse (contact an Attorney; we are Mechanics, NOT attorneys). Consequently, if the vehicle is still under warranty, to save yourself money do be sure to seek a resolution from the dealer. If the vehicle is not under warranty, obviously a certified Mechanic from YourMechanic could identify the electrical fault and resolve this for you. If you want to go that route, please simply request a no start diagnostic -electrical system and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Okay so when I turn my lights on at night my brake lights do not work, when I don’t have my lights on they work fine.
ANSWER : Hi there. Based on your inquiry, it’s highly probable that you have a damaged light switch or some electrical fault inside the turn signal relay. However, it’s also possible that the brake switch above the brake pedal could also be the source of your problem. Due to the fact that multiple electrical components might be causing this issue, it’s a smart idea to first have a professional mobile mechanic complete a brake lights are not working inspection, so they can determine what’s causing all of these issues and recommend the right repairs.

2005 Chrysler 300C changed battery and alternator. Car started, ran, and then battery light came on. Shut car off and wouldn’t start.
ANSWER : Hi. There is a couple of things that could be wrong here. The battery or alternator that was just installed could be defective. Theses parts need to be tested for proper operation. There also could be a fuse, fusible link, or wiring for the battery or charging system that is blown or broken causing the battery light to come on.

The codes that you have will cause the car to shut down, run rough, or not start at all. The crankshaft sensor and camshaft sensor should be replaced. I suggest having a certified technician from YourMechanic come diagnose the charging system and check engine codes to help you proceed with correct repairs.

Driving, then engine/oil light turns on, steering locks up, car dies; but just fine after turning off than on.
ANSWER : Any time loss of steering, or power assist to the steering is lost, it can be a safety issue and should be looked into as soon as possible. If the oil light and/or check engine light are flashing before it stalls, it can be a few different issues causing this. Also, a fault code may be stored in the system. Warning lights flashing after the engine stalls is normal. Most engine control units monitor readings from the oil pressure switch as well as the dozens of other sensors. Make sure the engine oil level is correct. If the oil pressure switch is intermittently losing it’s signal, then the ecu may think there is no engine oil pressure and shut down as a safety measure.

Have a certified technician look into the engine stalling as soon as possible. Losing steering and brake assist can be a safety hazard.