p2646
Moderate
Honda · SUVs
VTEC Oil Pressure Switch Circuit Low Voltage
Quick Answer
Error code P2646 on your Honda SUVs means: VTEC Oil Pressure Switch Circuit Low Voltage. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Low engine oil level or low oil pressure
  2. Faulty VTEC oil pressure switch
  3. Clogged VTEC solenoid filter/screen restricting oil flow
  4. Wiring short to ground in the VTEC oil pressure switch circuit
  5. Worn engine bearings causing low oil pressure at VTEC engagement RPM
How to Fix It
1
Check engine oil level and condition; change oil and filter if overdue or degraded
2
Remove and clean the VTEC solenoid filter/screen for debris or sludge buildup
3
Test the VTEC oil pressure switch by measuring voltage at the connector; it should switch from low to high when VTEC engages
4
Inspect the oil pressure switch wiring for shorts to ground, chafing, or damaged insulation
5
Replace the VTEC oil pressure switch if it does not toggle properly under oil pressure
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
VTEC oil pressure switch
VTEC solenoid filter/screen
VTEC solenoid gasket
Engine oil and filter
Related Error Codes
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