What should the voltage be on a GM alternator?
Ideal Voltage Output Ideally, the GM alternator should be putting out anywhere between 13.5 and 14.5 volts. A voltage regulator helps regulate the voltage that an alternator provides. If the voltage dips below the optimal range, then the regulator kicks in to get the alternator to make more voltage.
How does a voltage regulator work on an alternator?
A voltage regulator helps regulate the voltage that an alternator provides. If the voltage dips below the optimal range, then the regulator kicks in to get the alternator to make more voltage. The opposite happens when voltage levels read too high.
What does high voltage mean on car regulator?
Higher than Usual Voltage A high voltage reading, typically above 15 volts, indicates a problem. Though the regulator is designed to protect electrical components of the vehicle, sometimes it does fail.
Ideal Voltage Output Ideally, the GM alternator should be putting out anywhere between 13.5 and 14.5 volts. A voltage regulator helps regulate the voltage that an alternator provides. If the voltage dips below the optimal range, then the regulator kicks in to get the alternator to make more voltage.
A voltage regulator helps regulate the voltage that an alternator provides. If the voltage dips below the optimal range, then the regulator kicks in to get the alternator to make more voltage. The opposite happens when voltage levels read too high.
Higher than Usual Voltage A high voltage reading, typically above 15 volts, indicates a problem. Though the regulator is designed to protect electrical components of the vehicle, sometimes it does fail.
GM typically runs a fusible link wire between them for overload protection and they can go bad, mimicking a bad alternator. A voltage drop of .25 volts or less is Ok and the alternator is bad. A voltage drop of .5 volts or more means the wire is bad.
Why does the Volt gauge go up and down?
The voltage always fluctuates, goes up and down depending on how much current is being used by the accessories, and the engine rpm, the charge state of the battery, the ambient temperate, all affect the voltage. Fluctuation is normal, it’s like the stock market.
What to do if your alternator has low voltage?
Put the black multimeter probe on the negative battery terminal (if possible dig it into the battery post, not the terminal). Put the red probe on the alternator case. Your looking for the voltage to be below about 0.5v. If the voltage is higher than that examine all the negative cabling for problems. Preform the same test with the positive side.
What should the voltage be on a bat alternator?
Measure the voltage across the battery and the big bat alternator terminal to alternator case. There are two things that you are looking for. The charging voltage should be between 13.9v to 14.4v. Also the voltage at the battery and the voltage at the alternator should be within 0.5v of each other.
GM typically runs a fusible link wire between them for overload protection and they can go bad, mimicking a bad alternator. A voltage drop of .25 volts or less is Ok and the alternator is bad. A voltage drop of .5 volts or more means the wire is bad.
The voltage always fluctuates, goes up and down depending on how much current is being used by the accessories, and the engine rpm, the charge state of the battery, the ambient temperate, all affect the voltage. Fluctuation is normal, it’s like the stock market.
Why does the dash gauge switch from battery to alternator?
OK now that is starting to make sense. If the dash gauge switches over from reading battery voltage to alternator voltage after the engine starts, and there’s a diode between the alt. output and the battery, it would explain a lot. I will take readings at the alternator and let you know what I find.
How does a voltage drop test work on a car?
A voltage drop test will assess voltage losses at the battery, the alternator and the starter. 1) With the voltmeter connected to battery, and key and engine off, record a “base” voltage reading. (Your battery should have a minimum of 12.4 volts.)
When is a voltage regulator bad for an alternator?
When your test shows a steady or intermittent high or low voltage output, the voltage regulator is possibly bad. Most voltage regulators fail by allowing a high voltage output, though. However, before going any further, check that all the connections to the alternator and battery are good and clean as described in the next section.
Is the alternator charging at 18 volts or 23?
Alternator charging at 18 volts, replaced alt and didn’t fix. Have read some other answers on similar problems, blue wire reads 18 volts, green wire reads.23 volts? have the same problem?
Why does my alternator get higher than base voltage?
You should get 0.5 to 2 volts higher than base voltage. If you are getting more than 2 volts above base voltage, most likely your alternator is over-charging the battery or the battery is faulty. Other potential problems are a faulty voltage regulator or a problem in the charging system wiring.
Why is my mercury 150 hp alternator not charging?
Mercury 150 hp alternator is not charging battery at 14 volts. After charging battery and running engine for a time engine just quit and will not start as if battery is dead. Mechanic’s Assistant: Sometimes things that you think will be really complicated end up being easy to fix.
Why is my alternator not charging at 14 volts?
Mercury 150 hp alternator is not charging battery at 14 volts. After charging battery and running engine for a time My batteries on my boat are giving me 12.2v. Once I turn the
What to do if your alternator is overcharging?
To verify this, with the ignition switch off, connect your ohm meter with small jumper wires so you don’t have to hold onto the probes. Connect one to a paint-free point on the engine, and the other one to the green wire. Actually, you can use either small terminal on the back of the alternator.
Where is the green wire on an alternator?
Connect one to a paint-free point on the engine, and the other one to the green wire. Actually, you can use either small terminal on the back of the alternator. The resistance between those two terminals is only four ohms, but be aware, it is common for them to read open circuit when the rotor is not spinning.
Can a loose tensioner cause an alternator to fail?
Nevertheless, if the tensioner wears out, it can cause alternator problems (loose belt or worse, the belt can totally fall of the alternator pulley). Broken or damaged wires This happens mostly in older cars duo to material fatigue of the electric installation.
What causes an alternator to go over base voltage?
If you are getting more than 2 volts above base voltage, most likely your alternator is over-charging the battery or the battery is faulty. Other potential problems are a faulty voltage regulator or a problem in the charging system wiring.
Is it normal for an alternator to not charge?
Still, it’s perfectly normal for others to see the alternator not charge at all intermittently. One test is not enough if you are diagnosing a charging system problem. All too often, the alternator is condemned as the source of the problem if only battery voltage is present with the engine running.
How can I check the output of my alternator?
Step 1 Check the amperes your alternator produces if it operates correctly. Wear protective gloves as you need to be in close contact to the car battery to check the ampere output from your alternator. Open the car’s hood and secure it. Use a multimeter and set it to read amperes. Look at the display on the multimeter.
How many Watts Does a car alternator produce?
It would appear that the common word of wisdom is that car alternators provide 50A of output. I actually looked at the supposed specs for my 2008 Jetta 2.5L on the internet — a compact car — and it would appear that it might be rated for 140A 14V (in ideal conditions?), which is a lot of power — 1960 watts!
What does it mean when your alternator is malfunctioning?
Cars with an iDrive system will display alternator malfunction warning messages such as vehicle battery charge low or vehicle battery discharged while stopped. Once the voltage output is within the proper range again, the warning light will turn off.
What happens when you use a high output alternator?
And it basically operates off of supply and demand. That is, your alternator will only supply the amount of amperage a particular component demands—and no more. So high-output alternators will not harm your components or charging system, no matter how high you go with the amps.
When does an alternator need to be charged?
Alternator output is on demand when there are loads detected or the battery needs to be charged. Depending on ambient temperature, charging voltage varies.