Internal Control Module Random Access Memory (RAM) Error
Common Symptoms
- Check Engine Light or Malfunction Indicator Lamp illuminated
- Engine may not start or cranks but fails to start
- Intermittent stalling or engine shutdown while driving
- Loss of stored engine parameters or driveability issues
- Other fault codes may set simultaneously
- Vehicle may enter limp mode with reduced performance
Most Likely Root Causes
- Failing or degraded Engine Control Module (ECM) or Powertrain Control Module (PCM)
- Low or unstable battery voltage affecting control module memory
- Corroded or loose control module power or ground connections
- Software corruption or incomplete ECM/PCM programming or reflash
- Water intrusion or physical damage to the control module
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Component Location
The Engine Control Module or Powertrain Control Module is typically located in the engine compartment, under the dashboard, or near the firewall depending on vehicle make and model.
Manufacturer Notes
Internal RAM errors often indicate imminent control module failure and may require module replacement if code persists after voltage and connection verification.
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