Guided diagnostic workflow

FOLLOW THE
EVIDENCE.

Choose a symptom, run the least-invasive checks first and let each result select the next test. Vehicle-specific service information always wins.

01 / NO-START

Battery → crank speed → fuel/spark → timing

Start with battery state and cranking voltage. If it does not crank, test start-control and high-current paths. If it cranks, verify RPM, fuel pressure, injector command and ignition before timing or compression.

OPEN RELATED GUIDE →
02 / MISFIRE

Identify → compare → isolate → confirm

Capture codes and freeze-frame data, then compare cylinder contribution. Check ignition and injector control under load before compression or leak-down testing.

OPEN RELATED GUIDE →
03 / CHARGING

Battery → connections → command → output → ripple

Prove battery health, belt condition and voltage drop first. Compare commanded and actual charging voltage under load, then check ripple and current.

OPEN RELATED GUIDE →
04 / NETWORK FAULT

Power/ground → topology → termination → traffic

Check module powers and grounds before condemning a bus. Measure resistance unpowered, then scope both conductors to separate wiring faults from missing or transmitting nodes.

OPEN RELATED GUIDE →

Every branch

VERIFY THE
FOUNDATION.

  1. Confirm the complaint and operating conditions.
  2. Check battery state, powers, grounds and fuses under load.
  3. Measure the circuit before replacing a component.
  4. Repeat the test after repair and document the result.