Crazy high voltage readings LG refrigerator

[infuzeyou]

New to the forum, tech with 4yrs experience just getting back into the field after 11 years in the military, so playing catch-up on new stuff.

On LG refrigerators with the linear compressors with no cooling, I've been consistently reading anywhere between 600-1500 VAC on the CON201 terminals to the compressor, whether the connecter is hooked up or not. Several of my fellow techs have seen this as well. LG says the max VAC output to the comp should be ~180VAC. I've never had any issues with my Fieldpiece meter. Am I doing something wrong or is my meter insufficient for LGs?

[Vance R]

The drive voltage to a linear compressor is normal 80 to 180 vac. The drive voltage is actual a square wave. Have seen about 300 vac as high with an inefficient compressor. My meter is a Fieldpiece SC46 and reads ok on LGs.

[Elio]

Did you realize the high voltage is normal ? Or what was the problem causing that high vac? I have the same issue 

[Vance R]

On 2/14/2020 at 3:57 PM, Vance R said:

Have seen about 300 vac as high with an inefficient compressor.

Answer is in the sentence. The board is driving the compressor harder to get cooling.