Engine Block Heater: Testing and Inspection
DIAGNOSIS AND TESTING-ENGINE BLOCK HEATERIf the unit does not operate (Fig. 5), possible causes can be either the power cord or the heater element. Test the power cord for continuity with a 110-volt voltmeter or 110-volt test light. Test heater element continuity with an ohmmeter or a 12-volt test light.
CAUTION: To prevent damage, the power cord must be secured in it's retainer clips and away from any components that may cause abrasion or damage, such as linkages, exhaust components, etc.