Car alternator malfunctions: facts and do-it-yourself instructions!

The alternator (or dynamo/alternator) converts the engine's mechanical energy into electrical energy, charging the battery and keeping it charged even when the headlights, radio, and heated seats are on. A faulty alternator can quickly become a problem as the ignition is started via the battery.

Generator in detail

The generator is not a wear part . Modern alternators have very long service life and almost never break.

However, damage and defects can occur in any component. In this case, it is better to replace the generator than to repair it.

Symptoms of a generator malfunction

There are several clear signs of a possible alternator malfunction. . If one of these signs appears, the generator must be checked immediately.

• The first sign are starting difficulties, meaning that it takes several attempts to start the engine.
• Another sign - discharging battery. If a new battery dies shortly after installation, this is usually due to a faulty alternator.
• If the battery indicator on the dashboard is on , the problem may be in the dynamo.

Possible defects

The generator and connected power supply have four weaknesses where the greatest number of faults occur. It:

1. The dynamo itself 2. Charge regulator 3. Cables and plugs 4. V-belt

1. Generator

If the alternator is faulty, the carbon brushes are most likely worn out. This can be eliminated only by a complete replacement of the generator.

2. Charge regulator

Very often, the charge regulator is responsible for the malfunction of the generator. It regulates the flow of electricity from the generator. If it is defective, it can only be properly checked and serviced in a garage. In most cases, replacement is the only solution.

3. Plugs and cables

The cables and plugs connecting the alternator and battery may be defective. A torn or frayed cable can weaken or even interrupt the power supply.

4. V-belt

If the V-belt is worn or loose , the power flow between the generator and the engine is weak. The generator is serviceable, but is no longer able to receive kinetic energy from the engine.

Garage or do-it-yourself replacement?

Replacing an alternator is not an easy task that any non-specialist can do. . In particular, in view of many different damage factors it is recommended to consult the garage. It's always a matter of budget, of course. . In a garage, a dynamo replacement, including a spare part, costs up to €800 (±£700) or more .

Provided that you have the necessary tools at home and dare to replace them, you can save a lot of money .

Phased generator replacement

Alternator replacement depends on the vehicle. The reason for this lies in the different designs of engines and engine compartments. First, the generator must be found in the engine bay. So the steps may vary .

disconnect the battery find a generator remove cover if necessary remove other parts if they block access to the generator loosen the V-belt tensioner disconnect the power and ground cables from the generator unscrew and remove the mounting bolts remove the generator. compare the new alternator in plain sight with the old one. perform all disassembly steps in reverse order. Observe the specified tightening torque and belt tension.

Avoid the following mistakes

• When disassembling a dynamo, it is important to remember which connections are where. If necessary document disassembly with photos and mark individual components .
• These delicate operations in the engine require the utmost care. Always make sure that the bolt torques are correct. .
• The spare part must be installed safely and securely and must not come loose when the engine is running . The same applies to the tension of the V-belt. There are also precise instructions that must be followed.