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Engine Lubrication System Trouble In General: Inspection

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Before performing diagnostics, make sure that the engine oil level is correct and no oil leakage exists.

Trouble Possible cause Corrective action
Warning light remains ON. a. Oil pressure switch failure
  • Cracked diaphragm or oil leakage within switch
Replace.
  • Broken spring or seized contacts
Replace.
b. Low oil pressure
  • Clogging of oil filter
Replace.
  • Malfunction of oil by-pass valve in oil filter
Replace.
  • Clogged oil passage
Clean.
  • Excessive tip clearance and side clearance of oil pump rotor
Replace.
  • Clogged oil strainer or broken pipe
Clean or replace.
c. No oil pressure
  • Insufficient engine oil (degradation, etc.)
Replace.
  • Broken pipe of oil strainer
Replace.
  • Stuck oil pump rotor
Replace.
Warning light does not illuminate. a. Malfunction of combination meter Replace.
b. Poor contact of switch contact points Replace.
c. Disconnection of wiring Repair.
Warning light flickers momentarily. a. Defective terminal contact Repair.
b. Defective wiring harness Repair.
c. Oil pressure switch failure
  • Cracked diaphragm or oil leakage within switch
Replace.
  • Broken spring or seized contacts
Replace.
d. Low oil pressure
  • Clogging of oil filter
Replace.
  • Malfunction of oil by-pass valve in oil filter
Replace.
  • Clogged oil passage
Clean.
  • Excessive tip clearance and side clearance of oil pump rotor
Replace.
  • Clogged oil strainer or broken pipe
Clean or replace.