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How to test for electrolysis


According to MACS member Spectra Premium Industries, a  North American manufacturer  of many aftermarket A/C and engine cooling system parts, testing for electrolysis is a simple task. Use a digital volt ohms meter (DVOM). Set your meter to DC volts. With the engine off, hook the negative lead from the meter to the negative post of the battery. Submerge the positive lead of the meter in the coolant, touching only the coolant. If the lead touches any metal part or the radiator or overflow container, the reading will be incorrect.
Check the readings with the engine off. Start the engine, take the readings while cranking and while running, any voltage higher than 3/10 of a volt will accelerate the deterioration of an aluminum radiator and heater core.
Inspect under hood ground circuits. If the problem cannot be found, remove one fuse at a time until voltage drops and verify that specific circuit. If stray current is detected,
the coolant must be flushed and replaced, as the aluminum corrosion inhibitors will be destroyed.
When having your mobile A/C system professionally serviced, insist on proper repair procedures and quality replacement parts. Insist on recovery and recycling so that refrigerant can be reused and not released into the atmosphere.
You can E-mail us at or visit to find a Mobile Air Conditioning Society repair shop in your area. Visit to find out more about your car’s mobile A/C and engine cooling system.
Many thanks to MACS member Spectra Premium Industries for this post.

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