Engine Cooling System: Diagnosis Ford Explorer V

Related Module DTC Chart(s)

PCM DTC CHART

Symptom Chart: Engine Cooling

Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to DIAGNOSTIC METHODS for information regarding Ford-specific diagnostic practices.

Illustration Name Number TKITNumber 3-WAY HD ANTIFREEZE COOLANT TEST KIT = 1 BTL. OF 50 STRIPS AND 1 KIT 328-00001 - COOLANT/BATTERY REFRACTOMETER (FAHRENHEIT) ROB75240

Scheme 1

Scheme 2

Inspection and Verification

Note. The cooling system is filled with Motorcraft® Specialty Green Engine Coolant or. Always fill the cooling system with the manufacturer's specified coolant. Chemically flush the cooling system if a non-specified coolant has been used. REFER to Cooling System Flushing . Failure to follow these instructions may damage the engine or cooling system.

Note. The engine cooling system is filled with Motorcraft® Specialty Green Engine Coolant or. Mixing coolant types degrades the corrosion protection of the coolant. Do not mix coolant types. Failure to follow these instructions may damage the engine or cooling system.

Note. Motorcraft® Specialty Green Engine Coolant is very sensitive to light. Do NOT allow this product to be exposed to ANY LIGHT for more than a day or two. Extended light exposure causes this product to degrade.

Note. During normal vehicle operation, may change color from orange to pink or light red. As long as the engine coolant is clear and uncontaminated, this color change does not indicate the engine coolant has degraded nor does it require the engine coolant to be drained, the system to be flushed, or the engine coolant to be replaced.

Note. Vehicles have the pressure relief cap on the degas bottle and no radiator cap.

1. Verify the customer concern.
2. Visually check the engine coolant level at the degas bottle when the system is cold.
3. Make sure the pressure relief cap is installed correctly.
4. Record any cooling system DTCs retrieved. REFER to «Related Module DTC Chart(s)»(ref-517561-S34503902002012121200000) .
5. NOTE: Take note of any coolant odor or steam coming from cooling system components. If the system coolant is filled correctly and no DTCs associated with fail-safe cooling are retrieved, verify the customer concern by operating the engine to duplicate the condition.
6. Visually inspect for obvious signs of any mechanical or electrical damage. VISUAL INSPECTION CHART - MECHANICAL / ELECTRICAL Mechanical Electrical Leaks or weeps at: Hoses Tubes Clamp joints Gaskets O-rings Thermostat coolant connection Radiator Pressure relief cap Coolant pump Oil cooler (may leak internally or externally) Heater core (wet floor or coolant odor in vehicle) Degas bottle Cylinder block core plugs Cylinder head core plugs Block heater (if equipped) Turbocharger - 2.0L GTDI Cracked or damaged: Hoses Tubes Hose clamps Thermostat coolant connection Radiator Pressure relief cap Cooling fan Coolant pump Oil cooler Degas bottle Cylinder block core plugs Cylinder head core plugs Block heater (if equipped) Turbocharger - 2.0L GTDI Restricted airflow through the A/C condenser/radiator Excessive white or light gray exhaust smoke (may have burnt coolant odor) Coolant in engine oil Engine oil in coolant Inoperative or damaged: Electric cooling fan Wiring, connectors, relays or modules CHT sensor VSS
7. If the inspection reveals an obvious concern that can be readily identified, repair it as necessary. Test the system for normal operation.
8. Inspect the coolant condition. Inspect the coolant color. NOTE: The cooling system is filled with Motorcraft® Specialty Green Engine Coolant or. Always fill the cooling system with the manufacturer's specified coolant. If a non-specified coolant has been used the cooling system must be chemically flushed. REFER to «Cooling System Flushing»(ref-517561-S03978197402012121200000) . Failure to follow these instructions may damage the engine or cooling system. NOTE: The engine cooling system is filled with Motorcraft® Specialty Green Engine Coolant or. Mixing coolant types degrades the corrosion protection of the coolant. Do not mix coolant types. Failure to follow these instructions may damage the engine or cooling system. NOTE: Motorcraft® Specialty Green Engine Coolant is very sensitive to light. Do NOT allow this product to be exposed to ANY LIGHT for more than a day or two. Extended light exposure causes this product to degrade. NOTE: During normal vehicle operation, may change color from orange to pink or light red. As long as the engine coolant is clear and uncontaminated, this color change does not indicate the engine coolant has degraded nor does it require the engine coolant to be drained, the system to be flushed, or the engine coolant to be replaced. If Motorcraft® Specialty Green Engine Coolant or has a clear or pale color, this indicates higher water content than required. Test the engine coolant freezing point range with ROB75240. The freezing point should be in the range -50 C (-58 F) to -26.1 C (-15 F). If the vehicle is driven in cold climates less than -36.7 C (-34 F), it may be necessary to increase the coolant concentration to get adequate freeze protection. Recommended coolant concentration is 50/50 engine coolant to distilled water. Discoloration of may indicate that incorrect coolant may have been added to the system. Use of incorrect (green or yellow) coolant degrades the corrosion protection of. Addition of Motorcraft® Specialty Green Engine Coolant may cause the color to appear to be a murky green-brown color. The addition of Motorcraft® Premium Gold Engine Coolant, however, may not change the color or appearance of the orange colored coolant. Detection of contamination with Motorcraft® Premium Gold Engine Coolant is determined by the presence of nitrite. If contamination with Motorcraft® Premium Gold Engine Coolant is suspected, test the coolant with 328-00001 . Follow the directions in the kit with regard to nitrite testing. If nitrite is present, flush the system and refill with the correct mixture of distilled water and. REFER to «Cooling System Flushing»(ref-517561-S03978197402012121200000) . A darker color with the presence of debris could indicate a commercially available stop-leak may have been used and could result in loss of coolant flow to critical parts of the engine. If sediment is present in the coolant sample, flush the system and refill with the correct mixture of distilled water and engine coolant. REFER to «Cooling System Flushing»(ref-517561-S03978197402012121200000) . A light or reddish brown color indicates that rust may be present in the cooling system. Flush the system and refill with the correct mixture of distilled water and engine coolant. REFER to «Cooling System Flushing»(ref-517561-S03978197402012121200000) . An iridescent sheen on top of the coolant could indicate a trace of oil is entering the system. For information on engine diagnosis, REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) . Flush the system and refill with the correct mixture of distilled water and engine coolant. REFER to «Cooling System Flushing»(ref-517561-S03978197402012121200000) . A milky brown color may indicate that engine oil is entering the cooling system. Pressure test the cooling system. REFER to «Cooling System Pressure Test»(ref-517561-S40650065622012121200000) . If engine oil is suspected, the cause of the leak may be internal to the engine. For engine diagnosis, REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) . Flush the system and refill with the correct mixture of distilled water and engine coolant. REFER to «Cooling System Flushing»(ref-517561-S03978197402012121200000) . If the engine coolant appearance is acceptable, test the engine coolant freezing point range with ROB75240. The freezing point should be in the range of -50 C (-58 F) to -26.1 C (-15 F). If the vehicle is driven in cold climates less than -36.7 C (-34 F), it may be necessary to increase the coolant concentration to get adequate freeze protection. Recommended coolant concentration is 50/50 engine coolant to distilled water. Maximum coolant concentration is 60/40 for cold weather areas. Minimum coolant concentration is 40/60 for warm weather areas. Adjust coolant range and level if necessary: If coolant is low, add specified coolant mixture only. If the engine coolant tests too weak, remove some of the engine coolant and add undiluted engine coolant until the readings are within acceptable levels. If the engine coolant tests strong, remove some of the engine coolant and add distilled water until the readings are within acceptable levels.
9. If an obvious cause for an observed or reported concern is found, correct the cause and test the system for normal operation before proceeding to the Symptom Chart.

SYMPTOM CHART

Pinpoint Test

1. CARRY OUT INSPECTION AND VERIFICATION Carry out Inspection and Verification. REFER to «Symptom Chart(s)»(ref-517561-S06935444302012121200000) . Were any concerns found? Yes: REPAIR as needed. TEST the system for normal operation. No: GO to 2 .
2. CHECK THE ENGINE COOLANT LEVEL NOTE: Allow the engine to cool before checking the engine coolant level. Ignition OFF. Visually inspect the engine coolant level at the degas bottle. Is the engine coolant level within specifications? Yes: GO to 3 . No: ADJUST the engine coolant level as necessary. GO to 3 .
3. PRESSURE TEST THE ENGINE COOLING SYSTEM Pressure test the engine cooling system. REFER to «Cooling System Pressure Test»(ref-517561-S40650065622012121200000) . Does the engine cooling system leak externally? Yes: REPAIR or INSTALL new components. TEST the system for normal operation. No: GO to 4 .
4. CHECK THE ENGINE COOLANT FOR AN INTERNAL LEAK Inspect the engine coolant in the coolant expansion tank for signs of engine oil. Is engine oil evident in the coolant? Yes: REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) . No: GO to 5 .
5. CHECK THE ENGINE OIL FOR COOLANT Remove the oil level indicator from the engine. Is coolant evident in the oil? Yes: REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) e. No: GO to 6 .
6. CHECK THE COOLING SYSTEM FOR COMBUSTION GASES Using 105R0110 (-), following the instructions supplied with the tester, check the coolant for combustion gases. Are combustion gases present? Yes: REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) . No: The cooling system is operational.

1. CARRY OUT INSPECTION AND VERIFICATION Carry out Inspection and Verification. REFER to «Symptom Chart(s)»(ref-517561-S06935444302012121200000) . Were any concerns found? Yes: REPAIR as needed. TEST the system for normal operation. No: GO to 2 .
2. CHECK FOR AN AIRFLOW OBSTRUCTION Check the radiator or A/C condenser for an external obstruction such as leaves or cardboard. Is an obstruction present? Yes: REMOVE the obstruction. TEST the system for normal operation. No: GO to 3 .
3. CHECK THE ENGINE COOLANT LEVEL NOTE: Allow the engine to cool before checking the coolant level. Ignition OFF. Visually check the engine coolant level in the coolant expansion tank. Is the engine coolant level within specification? Yes: GO to 4 . No: ADJUST the engine coolant level as necessary. GO to 4 .
4. PRESSURE TEST THE ENGINE COOLING SYSTEM Pressure test the engine cooling system. REFER to «Cooling System Pressure Test»(ref-517561-S40650065622012121200000) . Does the engine cooling system leak externally? Yes: REPAIR or INSTALL new components. TEST the system for normal operation. No: GO to 5 .
5. CHECK THE ENGINE COOLANT FOR AN INTERNAL LEAK Inspect the engine coolant in the coolant expansion tank for signs of engine oil. Is engine oil evident in the coolant? Yes: REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) . No: GO to 6 .
6. CHECK THE ENGINE OIL FOR COOLANT Remove the oil level indicator from the engine. Is coolant evident in the oil? Yes: REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) . No: GO to 7 .
7. CHECK THE COOLING SYSTEM FOR COMBUSTION GASES Using 105R0110 (-), following the instructions supplied with the tester, check the coolant for combustion gases. Are combustion gases present? Yes: REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) . No: GO to 8 .
8. CHECK COOLANT CONDITION Check the coolant for dirt, rust or contamination and check the coolant concentration using ROB75240. Is the coolant condition OK? Yes: GO to 9 . No: FLUSH the engine cooling system. REFER to «Cooling System Flushing»(ref-517561-S03978197402012121200000) . TEST the system for normal operation.
9. CHECK THE ELECTRIC COOLING FAN OPERATION Start the engine. Place the climate control function selector in the MAX A/C position and the blower motor switch in the HI position. Did the electric cooling fan operate? Yes: GO to 10 . No: DIAGNOSE the electric cooling fan operation. REFER to the «SECTION 3: SYMPTOM CHARTS»(ref-477695-S11645663952012060700000) .
10. CHECK THE COOLANT PUMP OPERATION Start the engine. Allow the engine to run for 30 minutes. Place the climate control function selector in the MAX HEAT position. Feel the heater outlet hose. Is the heater outlet hose hot? Yes: GO to 11 . No: INSTALL a new coolant pump. TEST the system for normal operation.
11. CHECK THE THERMOSTAT OPERATION Start the engine. Allow the engine to run for 30 minutes. Feel the lower radiator hose. Is the lower radiator hose hot? Yes: CHECK the temperature gauge operation. REFER to «DIAGNOSTIC ROUTINE D»(ref-517585-S24964486332012121200000) : Incorrect Temperature Gauge Indication. No: GO to 12 .
12. VISUALLY INSPECT THE THERMOSTAT Carry out the thermostat visual inspection. REFER to «Thermostat»(ref-517561-S21930240722012121200000) . Is the thermostat damaged? Yes: INSTALL a new thermostat. TEST the system for normal operation. No: INSTALL a new thermostat. TEST the system for normal operation. If the engine still overheats, INSTALL a new radiator. TEST the system for normal operation.

1. CARRY OUT INSPECTION AND VERIFICATION Carry out Inspection and Verification. REFER to «Symptom Chart: Engine Cooling»(ref-517561-S24955008232012121200000) . Were any concerns found? Yes: REPAIR as needed. TEST the system for normal operation. No: GO to 2 .
2. CHECK FOR DTC P0125 or P0128 Check for DTC P0125 or P0128. Is DTC P0125 or P0128 present? Yes: GO to 3 . No: The cooling system is operational. If an inoperative temperature gauge is suspected, CHECK the temperature gauge operation. REFER to «DIAGNOSTIC ROUTINE D»(ref-517585-S24964486332012121200000) : Incorrect Temperature Gauge Indication. If an inoperative climate control system is suspected, CHECK the climate control system operation. REFER to «DIAGNOSTIC ROUTINE I»(ref-517581-S42354100302012121200000) : Climate Control System Functional Test, or REFER to «DIAGNOSTIC ROUTINE G»(ref-517582-S41739183562012121200000) : Climate Control System Functional Test. If any other PCM DTCs are retrieved, REFER to «DTC CHART: POWERTRAIN CONTROL MODULE (PCM)»(ref-517566-S33453853772012121200000) .
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. REFER to the «SECTION 3: SYMPTOM CHARTS»(ref-477695-S11645663952012060700000) . No: GO to 4 .
4. CHECK THE COOLANT LEVEL NOTE: Allow the engine to cool before checking the coolant level. Visually check the engine coolant level in the coolant expansion tank. Is the engine coolant level within specification? Yes: INSTALL a new thermostat. TEST the system for normal operation. No: REFER to «Diagnostic Routine A: Loss of Coolant»(ref-517561-S00145793142012121200000) .

Component Test

Note. Vehicles have the pressure relief cap on the degas bottle and no radiator cap.

Scheme 3

1. Turn the engine OFF.
2. Check the engine coolant level. Adjust the coolant level as necessary.
3. Attach 300-OTC014-R1068 to the degas bottle nipple and overflow hose. Install STN12270 to the quick connect fitting of the test adapter. NOTE: Do not pressurize the cooling system beyond the maximum pressure listed in the specifications table or cooling system components may be damaged. REFER to «General Specifications»(ref-517561-S40961936772012121200000) .
4. NOTE: If the plunger of the pressure tester is pressed too fast, an incorrect pressure reading results. Slowly press the plunger of the pressure test pump until the pressure gauge reading stops increasing and note the highest pressure reading obtained. If the pressure reading exceeds the maximum cap pressure listed in the specifications table, install a new pressure relief cap. REFER to «General Specifications»(ref-517561-S40961936772012121200000) .
5. If the system does not hold pressure, remove the pressure relief cap and wash it in clean water to dislodge all of the foreign material from the gasket. Check the sealing surface in the filler neck of the degas bottle for nicks or cuts. Use fine sandpaper or emery cloth to remove nicks and cuts. Place a shop cloth in the filler neck to prevent debris from falling into the degas bottle. If nicks or cuts are too deep to remove, install a new degas bottle. Install the pressure relief cap.
6. Pressurize the engine cooling system as described in Step 4. Observe the gauge reading for approximately 2 minutes. Pressure should not drop during this time. If the pressure drops, inspect for leaks and repair as necessary.
7. If no leaks are found and the pressure drops, the pressure relief cap may be leaking. Install a new pressure relief cap and retest the system.
8. If no leaks are found after a new pressure relief cap is installed, and the pressure drops, the leak may be internal to the engine. Inspect the coolant for engine oil and the engine oil for coolant. REFER to «SYMPTOM CHART: ENGINE PERFORMANCE»(ref-517560-S09879617192012121200000) .
9. Release the system pressure by loosening the pressure relief cap. Check the coolant level and adjust as necessary.

A new thermostat should be installed only after the following tests and checks have been carried out

1. REFER to «Diagnostic Routine A: Loss of Coolant»(ref-517561-S00145793142012121200000) , REFER to «Diagnostic Routine B: The Engine Overheats»(ref-517561-S06130519432012121200000) , or REFER to «Diagnostic Routine C: The Engine Does Not Reach Normal Operating Temperature»(ref-517561-S17054273682012121200000)
2. Thermostat visual inspection

1. Remove the thermostat.
2. Examine the thermostat for signs of damage including: Valve not fully seated (light visible through the valve) Foreign material lodged in the main valve Bent or broken frame or flange Bent or broken valve or valve stem Wax leaking from wax reservoir or a bulge in the reservoir Any other damage or distortion
3. NOTE: If no damage is found during the inspection, do not attempt to open the thermostat using hot water or other heat sources. This method is not an accurate means to test the function of the thermostat and may damage the thermostat. If damage is found during the inspection, remove any foreign material or broken pieces and install a new thermostat.
4. If no damage is found during the inspection, continue troubleshooting the system concern. REFER to «Symptom Chart: Engine Cooling»(ref-517561-S24955008232012121200000) .

Note. Never leak test an aluminum radiator in the same water that copper/brass radiators are tested in. Flux and caustic cleaners may be present in the cleaning tank and they will damage aluminum radiators.

Note. Clean the radiator before leak testing to avoid contamination of tank.

1. Leak test the radiator in clean water with air pressurized to the maximum pressure listed. REFER to «General Specifications»(ref-517561-S40961936772012121200000) .