Is the voltage regulator in the alternator?

The voltage regulator can be mounted inside or outside of the alternator housing. If the regulator is mounted outside (common on some Ford products) there will be a wiring harness connecting it to the alternator. The voltage regulator controls the field current applied to the spinning rotor inside the alternator.

What causes alternator voltage regulator failure?

They usually fail because they’re under rated for the constant current draw. Running the motor with the battery disconnected – or even a poor contact on the battery terminals – can also blow them. The voltage regulator controls the field current applied to the spinning rotor inside the alternator.

Can voltage regulator cause starting problems?

A bad voltage regulator may cause it to simply not work or behave erratically. You’re not likely to be able to start the car at all, but even if you could, it wouldn’t be wise to do so without knowing how fast you’re driving, how much fuel you have left, and other critical info.

Can a bad battery cause an alternator to over charge?

Make sure that all the connections to the alternator, remote voltage regulator (if applicable) and battery are clean, tight and in good condition. Check your battery or have it tested at your local auto parts store. A bad battery cell can cause the alternator to over-charge the good battery cells.

Can you test the battery with an alternator?

Click to expand… That’s battery cable trick. When cars had generators you could test the generator by running the car with the battery disconnected. It’s different with an alternator and with todays cars. You can spike the electronics very easily.

Why did my Honda alternator fail a test?

They hooked up the test tool and said that the battery was good, starter was good, but the alternator is bad because the voltage regulator test failed. I called the Honda dealer near me and ordered a new alternator. The wait time was 1 day.

Why is the voltage reading on my alternator going up?

While watching the voltmeter display, start wiggling wires at the back of the alternator, the battery, and the remote voltage regulator (if there is one). If the voltage reading on the meter display goes up while wiggling one of the wires, you’ve found a bad electrical wire or connection.

Can a battery voltage test be done on an alternator?

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. If this is the case, it only means that the alternator is not charging, but does not reveal why.

How can I tell if I have an alternator problem?

To differentiate an alternator problem from the battery, you will need to use a voltmeter to check for voltage. First, turn off the engine and check the battery voltage. A fully charged battery should have a reading of 12.65 volts. Next, turn on the engine and recheck the voltage. You should have a reading of 13.5 to 14.5 volts.