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Engine Lubrication System Trouble In General: Inspection

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.