Fault Code E02-startup – Wacker Neuson Series 2

Meaning: Incoming power is outside acceptable limits. This page focuses on cases where the code appears during startup.

Common causes

• Loose or damaged wiring/connector
• Connector corrosion, moisture intrusion, or contamination
• Out-of-range operating conditions
• Component wear or intermittent failure
• Improper installation or setup
• High inrush starting load (motors/compressors)
• Dirty air filter or restricted airflow
• Low battery/weak start circuit (if applicable)
• Cold-start conditions or sensor stabilization
• Short circuit or internal module failure

What to check first

1. Power down the unit before inspection and allow it to cool (if hot)
2. Disconnect loads and restart; reconnect one device at a time to identify surges
3. Verify connectors are seated and wiring is intact (no pinches/cuts/burn marks)
4. Confirm supply power is within specification for your unit
5. Remove debris and ensure proper ventilation/airflow
6. After correcting the suspected cause, power-cycle and retest
7. Verify oil level/type and fuel supply quality (as applicable)
8. If the issue occurs only at startup, verify stable power during start and allow a clean restart

Is it safe to keep running?

No. Stop operation and troubleshoot before continuing.

Reset guidance

After correcting the underlying issue, clear the fault by power-cycling the unit, then retest during startup. If the code returns, stop and escalate to service diagnostics.

When to call service

• The code returns immediately after basic checks
• There are visible signs of damage, overheating, or burning odor
• The unit will not start or shuts down repeatedly
• You are not comfortable performing electrical diagnostics safely

General reference only. Not affiliated with manufacturers. Meanings describe common patterns and may vary by exact model/version—always confirm with your model’s service manual.