This error is triggered when the ECU detects a high voltage somewhere in the charging system. It often points to an overcharging alternator, but can also be caused by problems elsewhere such as a bad voltage regulator, bad battery wiring, or corrosion at the battery terminals.
What are the symptoms of an overcharging alternator?
Check Engine Light
Might. You’re more likely to see the Check Engine Light. Manufacturers often link the red battery warning light to a low electrical output. An overcharging alternator results in a voltage that’s too high, so the battery light might not come on.
What causes overcharging battery?
You can also overcharge your battery with human error – that is, by not knowing how to use car battery chargers, using amp settings that are too high, or setting an incorrect voltage. If you have left your car battery charger unattended overnight, you can also overcharge it, which can cause damage to your battery.
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 would my alternator be overcharging? – Related Questions
Is 14.7 volts too high for alternator?
To fully charge in reasonable times, alternator output must be 14.2 V to 14.5 V as measured right across the battery posts. Above 14.5 volts charging voltage, batteries have a greatly increased tendency to release excessive acidic vapors, hydrogen gas, and to corrode things around the battery.
Is 15 volts too high for alternator?
A good alternator should maintain battery voltage between 13.9 and 14.8 volts (14.2 is optimum). Even worst-case, with all accessories turned on, there should be at least 13 volts at the battery.
Will a high-output alternator hurt my car?
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.
What should alternator output be at idle?
A good alternator should produce about 13.5 to 14.5 volts with the engine idling. If the voltage reading is low (12.5 volts or less), it indicates a charging problem but does not tell you what’s causing it.
What size alternator do I need for 3000 watt amp?
3000 watts / 12V = 250A. You’d need a 250A alternator to keep up with it.
Can an alternator overcharge a battery?
The build-up of hydrogen gas from an overcharging alternator causes your battery to swell. This also causes the battery to leak highly flammable liquid electrolyte, which is very dangerous. Please see a specialist right away if you notice this happening.
Voltage that is too high can cause premature failure of electrical and electronic components (e.g. circuit boards) due to overheating. The damage caused by overheating is cumulative and irreversible.
How much voltage is too much from an alternator?
If the charging keeps going up above 19V, you are in for expensive repairs. What causes a car alternator to put out low voltage? The most common cause is jump starting a car by revving your engine while the other person tries to crank their engine to start it.
How do I know if my alternator is faulty?
7 Signs of a Failing Alternator
Dim or Overly Bright Lights.
Dead Battery.
Slow or Malfunctioning Accessories.
Trouble Starting or Frequent Stalling.
Growling or Whining Noises.
Smell of Burning Rubber or Wires.
Battery Warning Light on Dash.
Can a blown fuse cause alternator problems?
Dead Battery
As was mentioned earlier, the alternator charges the battery while supplying the rest of the car with electricity. If the alternator’s fuse or fusible link is blown, the alternator will not be able to charge the battery.
How do you check an alternator without a multimeter?