I tested a variety of broken sensors, showing which test(s) they fail. There are three tests: Total Resistance, Voltage output, and Smooth voltage output. The last one is not prescribed by the factory repair manual (BGB). It's just common sense that the TCU will go nuts, if the voltage it sees as the arm sweeps behaves erratically! A digital VOM is fine to test total resistance and min/max voltage output. But useless to detect jumpy voltage. Even the analog VOM seems to miss the jumpy voltage on the video. The oscilloscope seems best to detect jumpy voltage output. Repair ideas - 1. Total Resistance: Too low likely points to water in the sensor (attracted by brake fluid). Too high may indicate breaks in the conductive strips. Maybe repairable with some conductive paint (?) 2. Voltage Output: Too high likely means water inside. Too low may mean the conductive strips are worn or dirty. Rubbing the conductive strip surfaces with #2 pencil may fix it. 3. Jumpy voltage output: Possibly due to dirty or worn conductive strip surface. Rubbing the conductive strip surfaces with #2 pencil may fix it. If it's due to breaks in the conductive surface, some conductive paint may fix it - but I've never tried. It would be difficult to get the surface to be smooth.
22 авг 2024
