OTC's Glow Plug Tester provides fault detection thru LED's for a quick analysis of short circuit, over current, normal operation, and open circuit/under current. The Glow Plug Tester allows for testing without removing the glow plug from the engine. Tester powers the glow plug to test it in it's operating state for a 'real world' analysis. Provides much greater accuracy than a cold resistance test which can miss short circuits. Tester uses a current measurement to accurately determine proper operation and check for short circuits. Value is at the core of the OTC tool and equipment portfolio. For a simple repair or the most complex drivability concern, these award-winning tools universally solve problems faster, and at better value, than any other product line available. Whether it's a specialty tool or unique piece of service equipment, OTC provides top solutions to modern automotive service challenges while increasing technicians' productivity and shop profits.