Cause
Poor module ground connection
An earth strap or stud that has corroded, loosened, or been left off after other work. A module with a poor earth reports plausible but wrong readings across everything it measures, because every voltage it sees is referenced to that point.
Typically a moderate job.
Some of these codes mean you should stop driving
7 of the 65 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 (65)
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
- P0728 Engine Speed Input Circuit Intermittent Likely for this code High
- P0863 Transmission Control Module Communication Circuit Likely for this code High
- P0864 Transmission Control Module Communication Circuit Range/Performance Likely for this code High
- P0880 Transmission Control Module Power Input Signal Likely for this code High
- P0881 Transmission Control Module Power Input Signal Range/Performance Likely for this code High
- P0882 Transmission Control Module Power Input Signal Low Likely for this code High
- P0884 Transmission Control Module Power Input Signal Intermittent Likely for this code High
- P0A1A Generator Control Module Likely for this code Moderate
- P0A1D Hybrid/EV Powertrain Control Module A Likely for this code High
- P0A1F Battery Energy Control Module A Performance Likely for this code High
- P2107 Throttle Actuator A Control Module Processor Likely for this code Stop driving High
- P2244 O2 Sensor Reference Voltage Performance Bank 1 Sensor 1 Likely for this code High
- P2248 O2 Sensor Reference Voltage Performance Bank 2 Sensor 1 Likely for this code High
- P2669 Actuator Supply Voltage B Circuit/Open Likely for this code High
- P2670 Actuator Supply Voltage B Circuit Low Likely for this code High
- P2684 Actuator Supply Voltage C Circuit/Open Likely for this code High
- P2685 Actuator Supply Voltage C Circuit Low Likely for this code High
- P276A Electric/Auxiliary Transmission Fluid Pump B Motor Supply Voltage Circuit/Open Likely for this code Moderate
- P276B Electric/Auxiliary Transmission Fluid Pump B Motor Supply Voltage Circuit Low Likely for this code Moderate
- P276C Electric/Auxiliary Transmission Fluid Pump B Motor Supply Voltage Circuit High Likely for this code Moderate
- P276D Electric/Auxiliary Transmission Fluid Pump B Motor Current Likely for this code Moderate
- P276E Electric/Auxiliary Transmission Fluid Pump B Motor Current Low Likely for this code Moderate
- P276F Electric/Auxiliary Transmission Fluid Pump B Motor Current High Likely for this code Moderate
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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