The first step: check whether there is broken wire, wrong connection and short circuit in the connection part of each external conductor of generator, and measure whether there is battery voltage at B + point with voltmeter.
Step 2: turn the key door to the "on" position, but do not start the engine. At this time, use a voltmeter to measure the voltage at d + point and observe whether the charging indicator is bright.
Step 3: start the engine and measure the voltage of the engine B + point with a voltmeter, which should reach the following values.
Step 4: turn on some loads, such as lights
Step 5: turn on the air conditioner lights
At the third step, the generator has no voltage output. The following methods can be adopted to check. For the generator with excitation D + point, a 2.5mm2 wire can be led from the positive pole of the battery,
After starting the engine, click D + point with the other end (within 1s), and then measure whether there is voltage output at point B + with voltmeter. If so, check from step 3 to step 5
It can be judged that there is an open circuit in the charging indicator line of the whole vehicle (generally, the indicator lamp is damaged, the connector of the instrument panel rod is loose, and the circuit is open). If there is no voltage output, the generator has no voltage output
Power generation failure.