Features:
Designed To Work On 12V ONLY!
Disconnect the busbar or leads from the glow plugs to be tested;
Connect the RED battery clamp to the positive terminal of the battery, and the BLACK battery clamp to the negative terminal of the battery;
Push the contact plate in the end of the test probe onto the glow plug;
Terminate until the glow plug has warmed up. This might take between 3 and 20 seconds (Check manufacturers specs for exact warm-up time)
Check which LED is illuminated on the control panel;
Short Circuit---Defective glow plug
>16A---Defective glow plug (more than 3 seconds)
<7A---Defective glow plug (high resistance )
Open Circuit---Defective glow plug
Low Battery---Check source battery volts
NOTE: Even when all 4 glow plugs are open circuit, DO NOT assume this tool is faulty. The vehicle might be still started up with all 4 glow plugs being defective.