Generator testing steps

Step 1: Check all external generator wiring connections for broken wires, misconnections, or short circuits. Use a voltmeter to measure the battery voltage at point B+.

Step 2: Turn the key to the "On" position, but do not start the engine. Use a voltmeter to measure the voltage at point D+ and check whether the charging indicator is on.

Step 3: Start the engine and use a voltmeter to measure the voltage at point B+ on the engine. It should reach the following values:

Step 4: Turn on some loads, such as lights.

Step 5: Turn on major appliances, such as the air conditioner and lights.

If the generator has no voltage output during step 3, you can use the following method to check: For generators with an excitation point D+, run a 2.5mm² wire from the positive terminal of the battery. After starting the engine, briefly touch point D+ with the other end (for less than 1 second). Then use a voltmeter to measure for voltage output at point B+. If so, continue checking from steps 3 to 5. Also, check for a short circuit in the vehicle's charging indicator circuit (usually caused by a damaged indicator, a loose instrument panel connector, or a short circuit). If there is no voltage output, the generator is not generating power.