Error code
OBD2 P0642
OBD2P0642
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
Sensor Reference Voltage 'A' Circuit Low.
Severity
highDriving may be possible but could lead to engine damage if not addressed.
Summary
P0642 indicates that there is a low reference voltage issue in the knock control sensor circuit within the Engine Control Module (ECM).
Common Causes
- Defective Engine Control Module (ECM) related to knock control
Fixes
- Replace the Engine Control Module (ECM) related to knock control.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More OBD2 codes
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- P0605Internal Control Module Read Only Memory (ROM) Error
- P0606ECM/PCM Processor
- P0607Control Module Performance
- P0608Control Module VSS Output 'A'
- P0609Control Module VSS Output 'B'
- P0610Control Module Vehicle Options Error
- P0611Fuel Injector Control Module Performance