Trouble Shooting & Component Testing: Notes

NOTE: Before beginning trouble shooting procedures, check coolant level, thermostat operation and physical condition of radiator and fan blades.

Test drive vehicle (if possible) and inspect condition of all belts, hoses and mechanical components. Note symptoms. See COOLING SYSTEM SYMPTOMS table.

COOLING SYSTEM SYMPTOMS

Condition	Check
Fan Does Not Run	Power To Relays
Fan Runs Constantly In Low Speed	Low Fan Relay
No Low Fan Operation	Low Fan Relay
Fan Runs Constantly In High Speed	High Fan Relays
No High Fan Operation	High Fan Relays

NOTE: If failure is PCM-related, see appropriate TESTS W/CODES article in ENGINE PERFORMANCE.