Check the alternator with a test lamp: When diagnosing faults in an alternator, in addition to measuring with instruments, the test lamp method can also be used for inspection. When it has been determined that there is a non-charging fault, you can first not start the engine, turn on the ignition switch, connect one end of the test lamp's contact pin to the generator's magnetic field terminal, and touch the other end of the contact pin to the generator's casing. If the test lamp lights up, it indicates that the battery is conducting to the generator's magnetic field terminal. At this point, the wires on the armature terminal of the motor can be removed, the engine can be started, and the contact pin at one end of the test lamp can be touched to the armature terminal. Touch the generator housing with the other end and run the engine slightly above idle speed for a test (do not allow the speed to be too high). If the test light does not light up (see Figure 50), or the light is weak, it indicates that there is a fault inside the generator. Car front logo

1. Visual inspection: Carefully examine whether the wires of the generator, regulator, and ignition switch are loose, whether the generator is securely fixed, and whether the V-belt is loose or has oil stains and slippage, etc.

2. Check the regulator: Connect the two wire ends together (i.e., from the ignition switch to the regulator, and from the regulator to the generator magnetic field terminal wire). If the vehicle starts generating electricity, it indicates that the fault lies within the regulator (such as erosion of the platinum contact, weak tension of the contact spring, or burnout of the resistor, etc.).

Iii. Inspect the generator: Remove the wires from the magnetic field terminal of the generator, turn on the ignition switch, and scrape the removed wire ends against the magnetic field terminal. If there are blue-white sparks, it indicates that the circuit inside the magnetic field is in good condition. If there is no spark, it indicates that the carbon brush has not made good contact or the magnetic field coil is open-circuited.

4. Use a screwdriver to check at the rear end of the generator (at the 201 bearing cover) whether there is magnetic attraction. A normal generator should have a distinct suction force. If there is no suction force or the suction force is weak, it indicates that there is a fault in the excitation circuit.

Five, loose bearings, deformed end covers, and bent pivot shafts can all cause rubbing and "scraping", leading to coil erosion and preventing the generator from operating normally.