P0605 - Internal Control Module Read Only Memory (ROM) Error

The ECM detected an internal read-only memory fault.

Code Overview

The ECM detected an internal read-only memory fault.

Common Causes

• ECM failure
• Low voltage event
• Corroded ECM connections
• Wiring or power/ground issue

Diagnostic Steps

1. Check battery and charging system health
2. Inspect ECM power and ground connections
3. Look for water intrusion
4. Scan for other module or voltage-related faults

Likely Repairs & Cost Guides

Use test results to confirm the fault before pricing the repair.

Related OBD Codes

Browse the closest code-family pages when the same fault pattern often shows up nearby.

Next Steps

Move from the code to a diagnosis path, then into repair pricing once the fault is confirmed.