INSPECTION
| INSPECTION | 
Before performing diagnostics, make sure the engine oil level is correct and no oil leakage exists.
| Trouble | Possible cause | Corrective action | |
| 
        
         1. Warning light remains on.
        
         | 
       
        
         1) Oil pressure switch failure
        
         | 
       
        
         Cracked
diaphragm or oil leakage within switch
        
         | 
       
        
         Replace.
        
         | 
      
| 
        
         Broken
spring or seized contacts
        
         | 
       
        
         Replace.
        
         | 
      ||
| 
        
         2) Low oil pressure
        
         | 
       
        
         Clogged
oil filter
        
         | 
       
        
         Replace.
        
         | 
      |
| 
        
         Malfunction
of oil by-pass valve of oil filter
        
         | 
       
        
         Clean
or replace.
        
         | 
      ||
| 
        
         Malfunction
of oil relief valve of oil pump
        
         | 
       
        
         Clean
or replace.
        
         | 
      ||
| 
        
         Clogged
oil passage
        
         | 
       
        
         Clean.
        
         | 
      ||
| 
        
         Excessive
tip clearance and side clearance of oil pump rotor and gear
        
         | 
       
        
         Replace.
        
         | 
      ||
| 
        
         Clogged
oil strainer or broken pipe
        
         | 
       
        
         Clean
or replace.
        
         | 
      ||
| 
        
         3) No oil pressure
        
         | 
       
        
         Insufficient
engine oil
        
         | 
       
        
         Replenish.
        
         | 
      |
| 
        
         Broken
pipe of oil strainer
        
         | 
       
        
         Replace.
        
         | 
      ||
| 
        
         Stuck
oil pump rotor
        
         | 
       
        
         Replace.
        
         | 
      ||
| 
        
         2. Warning light does not go on.
        
         | 
       
        
         1) Malfunction of combination meter
        
         | 
       
        
         Replace.
        
         | 
      |
| 
        
         2) Poor contact of switch contact points
        
         | 
       
        
         Replace.
        
         | 
      ||
| 
        
         3) Disconnection of wiring
        
         | 
       
        
         Repair.
        
         | 
      ||
| 
        
         3. Warning light flickers momentarily.
        
         | 
       
        
         1) Poor contact at terminals
        
         | 
       
        
         Repair.
        
         | 
      |
| 
        
         2) Defective wiring harness
        
         | 
       
        
         Repair.
        
         | 
      ||
| 
        
         3) Low oil pressure
        
         | 
       
        
         Check
for the same possible causes as listed in 1.— 2).
        
         | 
      ||
