Diagnostic Procedure

WARNING:

Always allow the engine to cool before opening the cooling system. Do not unscrew the coolant pressure relief cap when the engine is operating or the cooling system is hot. The cooling system is under pressure; steam and hot liquid can come out forcefully when the cap is loosened slightly. Failure to follow these instructions may result in serious personal injury.

DIAGNOSTIC PROCEDURE CHART

PINPOINT TEST 3		THE ENGINE DOES NOT REACH NORMAL OPERATING TEMPERATURE
STEP	INSPECTION		ACTION
1	CARRY OUT INSPECTION AND VERIFICATION Carry out the inspection and verification procedure in Engine Cooling. Were any concerns found?	Yes	REPAIR as needed. TEST the system for normal operation.
1		No	GO to the next step.
2	CHECK FOR DTC P0125 OR P0128 NOTE: See QUICK TEST for correct scan tool hook-up procedure. Check for DTC P0125 or DTC P0128. Is DTC P0125 or DTC P0128 present?	Yes	GO to the next step.
2		No	The cooling system is operational. If an inoperative engine coolant temperature gauge is suspected, CHECK the engine coolant temperature gauge operation. See PINPOINT TEST 4: INCORRECT TEMPERATURE GAUGE INDICATION . If an inoperative climate control system is suspected, CHECK the climate control system operation. See SYMPTOM TROUBLESHOOTING CHART - CLIMATE CONTROL . If any other DTCs are retrieved, see DTC APPLICATION CHART .
3	CHECK THE ELECTRIC COOLING FAN OPERATION Allow the engine to cool. Make sure the A/C switch is OFF. Start the engine. Check the electric cooling fan. Is the electric cooling fan on all the time?	Yes	DIAGNOSE the electric cooling fan operation. See COOLING FAN MALFUNCTION .
3		No	GO to the next step.
4	CHECK THE COOLANT LEVEL NOTE: Allow the engine to cool before checking the coolant level. Visually check the engine coolant level in the degas bottle or coolant expansion tank. Is the engine coolant level within specification?	Yes	INSTALL a new thermostat. TEST the system for normal operation.
4		No	See PINPOINT TEST 1: LOSS OF COOLANT .