Fault Ground Circuits More Common Than You Think on Farm Machinery

Whenever you’re trying to track down an electrical problem in machinery, be sure to “think of faulty ground circuits,” urges Successful Farming’s Engine Man, Ray Bohacz. “Modern equipment is filled with electronics and is very ground-circuit sensitive,” he explained to farmers listening to him speak at the recent Commodity Classic Ag Connect Main Stage in San Antonio, Texas.

Anything electrical on engines, transmissions, planters, monitors, etc. can suffer from a faulty ground circuit. “No one can anticipate how a circuit will respond with a high-impedance ground,” Bohacz explains. “A voltage drop test, which is a simple test to perform, is the only way to accurately evaluate ground circuits. That test measures the ‘traffic jam’ of electrons in a circuit whereas an ohm test is inconclusive to detecting a faulty ground circuit. Simply checking for continuity isn’t enough to determine a faulty ground.” Bohacz explains that you should be suspicious of a ground circuit problem when:

• There is an intermittent electrical problem that makes no sense.
• When there is an electrical load-induced problem.
• If you are getting ECU codes, false readings, and mysterious electrical issues.