Path Checking & Circuit Tracing
Learn how to trace circuit paths on smartphone motherboards using continuity mode. This technique helps identify signal routes, ground connections, and component orientation.
1. Continuity Checking Basics
To begin tracing a circuit path, select the continuity mode on your digital multimeter. Place the red probe (+) at the starting component, test point or connector.
Use the black probe (-) to scan nearby components to find the next electrical connection.
- • Beep sound → Connection found
- • No beep → No connection
- • Move probe step-by-step to trace the path
2. Identifying Series vs Parallel Orientation
After identifying a connected component, determine whether it is connected in series or parallel.
Keep the multimeter in continuity mode. Place the black probe on GND and check both sides of the component with the red probe.
- • Beep on one side → Parallel component
- • No beep on both sides → Series component
3. Continuing the Trace
After determining the component orientation, continue tracing the circuit path using the following technique.
- Series Components:Move the red probe to the opposite side of the component and continue searching.
- Parallel Components:Keep the red probe on the same side and search nearby components.
Identifying all connected components along the way and continue the process until you reach the controlling IC or identify the fault.
Practical Technician Tip
Always trace circuits step-by-step. Combine continuity testing with motherboard schematics or boardview files to quickly identify signal paths and faults.