Testing Ground and Low Reference Circuits: Notes
WARNING: This page is about a different car, the 2020 Buick Regal TourX, 2020 Buick Regal, 2019 Buick Regal TourX, and 2019 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
The testing of ground and low reference circuits can be performed in multiple ways using multiple tools. Ground circuits may be tested in the following ways:
- Measuring resistance with a DMM
- Testing continuity with a test lamp
- Measuring voltage drop with a DMM
Each method of testing a ground or low reference circuit requires attention and understanding of the tools and results to ensure misdiagnosis does not occur based on the results:
- A DMM requires a more specific set of conditions on the vehicle when testing, but will accurately measure resistance. A DMM may not identify a ground or low reference circuit that maintains continuity, but is damaged and has compromised load carrying capability.
- Testing a ground or low reference circuit with a test lamp is a good way to quickly determine continuity, but may not identify all instances of excessive resistance.
- Measuring voltage drop with a DMM is a very accurate way to test a ground or low reference circuit, but requires the most time and effort to access components and ground locations.