Cause
Low system voltage
Supply below what the modules expect, from a tired battery, a charging fault or a bad connection at the battery posts. Modules short of voltage misbehave rather than switching off, so they record faults naming healthy parts all over the vehicle.
Fix the supply, clear the codes, drive, then read again. What comes back is real, and what does not was never a fault.
Typically an easy fix. Often worth checking before paying anyone to look.
Some of these codes mean you should stop driving
10 of the 82 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (82)
Codes where this is a likely explanation first, rather than merely a possible one.
- C0020 ABS Pump Motor Control Likely for this code Moderate
- C006C Stability System Likely for this code Moderate
- P00FD Battery B State of Charge Performance Likely for this code Moderate
- P052F Glow Plug Control Module 1 System Voltage Likely for this code Moderate
- P060C Internal Control Module Main Processor Performance Likely for this code Stop driving High
- P062F Internal Control Module EEPROM Error Likely for this code High
- P06E9 Engine Starter Performance Likely for this code Moderate
- P06EF Engine Restart Performance Likely for this code Moderate
- P0B0A Electric/Auxiliary Transmission Fluid Pump A Motor Supply Voltage Circuit Low Likely for this code Moderate
- P2029 Fuel Fired Heater Disabled Likely for this code Low
- P2209 NOx Sensor Heater Sense Circuit Range/Performance Bank 1 Sensor 1 Likely for this code Moderate
- P2222 NOx Sensor Heater Sense Circuit Range/Performance Bank 2 Likely for this code Moderate
- P2AF5 Starter Relay C Stuck On Likely for this code High
- U0061 Vehicle Communication Bus D (-) Low Likely for this code Moderate
- U0064 Vehicle Communication Bus E Likely for this code Moderate
- U0070 Vehicle Communication Bus E (-) Low Likely for this code Moderate
- U0076 Control Module Communication Bus D Off Likely for this code High
- U0111 Lost Communication With Battery Energy Control Module A Likely for this code Stop driving High
- U0112 Lost Communication With Battery Energy Control Module B Likely for this code Stop driving High
- U0120 Lost Communication With Starter/Generator Control Module Likely for this code Moderate
- U0131 Lost Communication With Power Steering Control Module A Likely for this code High
- U0469 Invalid Data Received From Starter/Generator Control Module Likely for this code Moderate
- U04B1 Invalid Data Received From Battery Monitor Module Likely for this code Moderate
- U3000 Control Module Likely for this code Moderate
- U3001 Control Module Improper Shutdown Performance Likely for this code Low
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
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