P06xx OBD-II Codes (P0600–P0699)
101 fault codes in the P06xx range. Click any code for causes, diagnostic steps, severity, and common fixes.
P0600 serious
Serial Communication Link Malfunction
P0601 critical
Internal Control Module Memory Check Sum Error
P0602 critical
Control Module Programming Error
P0603 moderate
Internal Control Module KAM Error
P0604 critical
Internal Control Module RAM Error
P0605 critical
Internal Control Module ROM Error
P0606 critical
ECM/PCM Processor Fault
P0607 critical
Control Module Performance
P0608 moderate
Control Module VSS Output A Malfunction
P0609 moderate
Control Module VSS Output B Malfunction
P0610 moderate
Control Module Vehicle Options Error
P0611 critical
Fuel Injector Control Module Performance
P0612 critical
Fuel Injector Control Module Relay Control
P0613 critical
TCM Processor
P0614 critical
ECM/TCM Incompatible
P0615 moderate
Starter Relay Circuit
P0616 moderate
Starter Relay Circuit Low
P0617 moderate
Starter Relay Circuit High
P0618 moderate
Alternative Fuel Control Module Performance
P0619 moderate
Alternative Fuel Control Module Memory Checksum Error
P0620 moderate
Generator Control Circuit
P0621 low
Generator Lamp L Control Circuit
P0622 moderate
Generator Field F Control Circuit
P0623 critical
Fuel Pump Control Module Performance
P0624 low
Fuel Cap Lamp Control Circuit
P0625 moderate
Generator Field Terminal Circuit Low
P0626 moderate
Generator Field Terminal Circuit High
P0627 critical
Fuel Pump A Control Circuit Open
P0628 critical
Fuel Pump A Control Circuit Low
P0629 moderate
Fuel Pump A Control Circuit High
P062F serious
P062F is a generic SAE J2012-defined powertrain trouble code meaning "Internal Control Module EEPROM Error." It is set when a control module (most often the PCM/ECM, sometimes the TCM or another controller) detects a fault in its own internal EEPROM (Electrically Erasable Programmable Read-Only Memory) during a self-test. The EEPROM holds calibration data, learned/adaptive values, and software parameters; when the module's internal checks find the stored or read-back data does not match expected values, it sets P062F. Because P062F flags a fault inside the module's own memory, it is treated as a serious internal-module fault. While the code definition is generic across OBD-II makes, the specific data stored in EEPROM differs by manufacturer: on many Toyota products it relates to fuel-injector calibration programming; on some Nissan and Chevrolet products it has been associated with transmission and throttle-control programming respectively. Some VW/Audi/Volvo platforms use code P1640 for an equivalent internal-EEPROM fault rather than P062F. A frequent real-world trigger is improper or incompatible reprogramming/tuning (performance chips or failed/interrupted flashes), as well as low or spiking system voltage and poor module grounding/wiring.
P0630 critical
VIN Not Programmed or Incompatible
P0631 critical
TCM Not Programmed
P0632 low
Odometer Not Programmed
P0633 critical
Immobilizer Key Not Programmed
P0634 moderate
PCM/ECM/TCM Internal Temperature Too High
P0635 moderate
Power Steering Control Circuit
P0636 moderate
Power Steering Control Circuit Low
P0637 moderate
Power Steering Control Circuit High
P0638 moderate
Throttle Actuator Control Range/Performance (Bank 1)
P0639 moderate
Throttle Actuator Control Range/Performance (Bank 2)
P0640 moderate
Intake Air Heater Control Circuit (Bank 1)
P0641 moderate
Intake Air Heater Control Circuit Open (Bank 1)
P0642 moderate
Intake Air Heater Control Circuit Low (Bank 1)
P0643 moderate
Intake Air Heater Control Circuit High (Bank 1)
P0644 low
Driver Display Serial Communication Circuit
P0645 low
AC Clutch Relay Control Circuit
P0646 low
AC Clutch Relay Control Circuit Low
P0647 low
AC Clutch Relay Control Circuit High
P0648 low
Immobilizer Lamp Control Circuit
P0649 low
Speed Control Lamp Control Circuit
P0650 low
Malfunction Indicator Lamp Control Circuit
P0651 moderate
Intake Air Heater Control Circuit (Bank 2)
P0652 critical
Reference Voltage B Circuit Open
P0653 critical
Reference Voltage B Circuit Low
P0654 low
Engine RPM Output Circuit
P0655 low
Engine Hot Lamp Output Control Circuit
P0656 low
Oil Level Output Circuit
P0657 moderate
Actuator Supply Voltage A Circuit Open
P0658 moderate
Actuator Supply Voltage A Circuit Low
P0659 moderate
Actuator Supply Voltage A Circuit High
P0660 low
Intake Manifold Tuning Valve Control Circuit Open (Bank 1)
P0661 low
Intake Manifold Tuning Valve Control Circuit Low (Bank 1)
P0662 low
Intake Manifold Tuning Valve Control Circuit High (Bank 1)
P0663 low
Intake Manifold Tuning Valve Control Circuit Open (Bank 2)
P0664 low
Intake Manifold Tuning Valve Control Circuit Low (Bank 2)
P0665 low
Intake Manifold Tuning Valve Control Circuit High (Bank 2)
P0666 moderate
PCM/ECM/TCM Internal Temperature Sensor B Circuit Range/Performance
P0667 moderate
PCM/ECM/TCM Internal Temperature Sensor B Circuit Low
P0668 moderate
PCM/ECM/TCM Internal Temperature Sensor B Circuit High
P0669 moderate
PCM/ECM/TCM Internal Temperature Too High B
P0670 moderate
Glow Plug Module Control Circuit
P0671 moderate
Cylinder 1 Glow Plug Circuit
P0672 moderate
Cylinder 2 Glow Plug Circuit
P0673 moderate
Cylinder 3 Glow Plug Circuit
P0674 moderate
Cylinder 4 Glow Plug Circuit
P0675 moderate
Cylinder 5 Glow Plug Circuit
P0676 moderate
Cylinder 6 Glow Plug Circuit
P0677 moderate
Cylinder 7 Glow Plug Circuit
P0678 moderate
Cylinder 8 Glow Plug Circuit
P0679 moderate
Cylinder 9 Glow Plug Circuit
P0680 moderate
Cylinder 10 Glow Plug Circuit
P0681 moderate
Cylinder 11 Glow Plug Circuit
P0682 moderate
Cylinder 12 Glow Plug Circuit
P0683 moderate
Glow Plug Control Module to PCM Communication Circuit
P0684 moderate
Glow Plug Control Module to PCM Communication Circuit Range/Performance
P0685 critical
ECM/PCM Power Relay Control Circuit Open
P0686 critical
ECM/PCM Power Relay Control Circuit Low
P0687 moderate
ECM/PCM Power Relay Control Circuit High
P0688 critical
ECM/PCM Power Relay Sense Circuit Open
P0689 critical
ECM/PCM Power Relay Sense Circuit Low
P0690 moderate
ECM/PCM Power Relay Sense Circuit High
P0691 moderate
Cooling Fan 1 Control Circuit Low
P0692 moderate
Cooling Fan 1 Control Circuit High
P0693 moderate
Cooling Fan 2 Control Circuit Low
P0694 moderate
Cooling Fan 2 Control Circuit High
P0695 moderate
Cooling Fan 3 Control Circuit Low
P0696 moderate
Cooling Fan 3 Control Circuit High
P0697 critical
Reference Voltage C Circuit Open
P0698 critical
Reference Voltage C Circuit Low
P0699 moderate
Reference Voltage C Circuit High