Toro Turf Equipment Diode and Battery Testing Procedure

When you encounter problems with the electrical system of your Toro turf equipment, the first step to fixing the problem is to determine what is causing it.  In another post of ours on alternator testing, we explained the procedure for a Briggs and Stratton engine, which will allow you to determine if you have a bad alternator.

Today, we’ll take a look at the diode and battery testing procedure for your electrical system—two other potential sources of problems.

Safety First

Whenever you are performing tests on a battery, be sure to follow all of the safety precautions recommended by the manufacturer. These will usually include things such as:

• Always holding the battery upright to avoid spilling electrolyte
• Service batteries in a well-ventilated area away from sources of heat
• Wear protective clothing and eyewear

Lead-acid batteries can cause injuries if not handled properly, so use common sense and put safety first at all times.

Battery Testing Procedure

When testing a battery, you’ll want to check both the voltage and the cold cranking amps using a multi-meter and a battery load tester.

To test the voltage using a multi-meter, turn the dial on the meter to the Volts DC setting. Connect the red wire from the meter to the positive terminal of the battery, and connect the black wire to the negative terminal. Check the voltage reading on the meter to ensure that it is at or above the rating for the battery (for example, 12 volts).

Now, test the cold cranking amps using the battery load tester.  Connect the red wire and black wires of the load tester to the positive and negative terminals of the battery, respectively.  Set the load tester to the cranking amps value printed on the battery (for example, 275 cranking amps).  Press the “test” button on the load tester to run the test.  If the test fails, press the test button again to check the volts and once more to check the cranking amps value.  This will allow you to determine why the battery failed the test.

Diode Testing Procedure

Diodes can be tested for proper operation using a multi-meter using the diode test mode.  To use the diode test mode of the multi-meter, simply move the dial to “diode test” and make sure that no voltage exists at the diode (this may require discharging the capacitors to get rid of any voltage in the system).  Take the positive and negative leads and connect the positive lead to the exposed side of the diode and the negative lead to the unexposed.  Check to make sure that the multi-meter registers an open line, and then reverse the leads.  You should now see resistance registering on the multi-meter.

If the multi-meter indicates an open line (OL) in both directions, or it indicates the same voltage drop in both directions, it means the diode is bad.

The battery and diode testing procedures are very simple and will allow you to quickly diagnose problems in the electrical system of your Toro equipment.