Multimeter Input Impedance and Automotive Diagnostics: Why a 10MΩ Meter Reads Different Than a 1MΩ Meter on Sensor Grounds
I spent a frustrating Tuesday afternoon in 2019 chasing an electrical ghost on a Euro 6 diesel bench harness. The symptom was a sporadic P0106—MAP sensor range/performance—that only appeared when the engine bay heat-soaked. The sensor was new. The wiring was new. The 5V reference was spot on. The problem was my multimeter. Not the sensor, not […]