Inspection and Verification
Engine Cooling
Inspection and Verification
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.
NOTICE: Early build vehicle cooling systems are filled with Motorcraft(R) Premium Gold Engine Coolant. Late build vehicle cooling systems are filled with Motorcraft(R) Specialty Orange Engine Coolant. Do not mix coolant types. Mixing coolant types degrades the corrosion protection of the coolant. Failure to follow these instructions may damage the engine or cooling system.
NOTE: During normal vehicle operation, Motorcraft(R) Specialty Orange Engine Coolant 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 the DTC Chart for DTC descriptions. Diagnostic Trouble Code Tests and Associated Procedures
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. NOTE: For the coolant flow diagram, refer to Engine Cooling Description and Operation in the Description and Operation.
Visually inspect for obvious signs of any mechanical or electrical concerns damage.
Visual Inspection Chart
7. If the inspection reveals an obvious concern that can be readily identified, repair it as necessary. Test the system for normal operation.
8. NOTICE: Early build vehicle cooling systems are filled with Motorcraft(R) Premium Gold Engine Coolant. Late build vehicle cooling systems are filled with Motorcraft(R) Specialty Orange Engine Coolant. Do not mix coolant types. Mixing coolant types degrades the corrosion protection of the coolant. Failure to follow these instructions may damage the engine or cooling system.
NOTE: During normal vehicle operation, Motorcraft(R) Specialty Orange Engine Coolant 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.
Inspect the coolant condition.
1. Inspect the coolant color.
- If Motorcraft(R) Premium Gold Engine Coolant has a clear or pale yellow color, this indicates higher water content than required. Test the engine coolant freezing point range with the Coolant/Battery Refractometer. The freezing point should be in the range -45°C to -23°C (-49°F to -9°F). If the vehicle is driven in cold climates less than -36°C (-33°F), it may be necessary to increase the coolant concentration to get adequate freeze protection. Recommended coolant concentration is 50/50 coolant to distilled water.
- NOTE: If cooling system stop leak pellets are used, Motorcraft(R) Premium Gold Engine Coolant may darken from yellow to golden tan.
For cooling systems filled with Motorcraft(R) Premium Gold Engine coolant, dark brown 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. Flush the system and refill with the correct mixture of Motorcraft(R) Premium Gold Engine Coolant and distilled water. Refer to Cooling System Flushing Cooling System Flushing.
- For cooling systems filled with Motorcraft(R) Premium Gold Engine coolant, a pale green color indicates incorrect coolant (green in color) has been added to the system. Use of incorrect (green in color) coolant degrades the corrosion protection of Motorcraft(R) Premium Gold Engine Coolant. If incorrect coolant has been added, flush the system and refill with the correct mixture of Motorcraft(R) Premium Gold Engine Coolant and distilled water. Refer to Cooling System Flushing Cooling System Flushing.
- For cooling systems filled with Motorcraft(R) Premium Gold Engine coolant, a red/orange color indicates incorrect coolant (red/orange in color) may have been added to the system. Use of incorrect (red/orange in color) coolant degrades the corrosion protection of Motorcraft(R) Premium Gold Engine Coolant. Flush the system and refill with the correct mixture of Motorcraft(R) Premium Gold Engine Coolant and distilled water. Refer to Cooling System Flushing Cooling System Flushing.
- For cooling systems filled with Motorcraft(R) Specialty Orange Engine Coolant, discoloration may indicate that incorrect coolant may have been added to the system. Use of incorrect (green or yellow in color) coolant degrades the corrosion protection of Motorcraft(R) Specialty Orange Engine Coolant. Addition of Motorcraft(R) Specialty Green Engine Coolant may cause the color to appear to be a murky green-brown color. The addition of Motorcraft(R) Premium Gold Coolant, however, may not change the color or appearance of the orange colored coolant. Detection of contamination with Premium Gold Engine Coolant is determined by the presence of nitrite. If contamination with Motorcraft(R) Premium Gold Engine Coolant is suspected, test the coolant with the 3-Way HD Antifreeze Coolant Test Kit. Follow the directions on the packaging. If the incorrect coolant has been added to the cooling system, flush the system and refill with the correct mixture of distilled water and Motorcraft(R) Specialty Orange Engine Coolant. Refer to Cooling System Flushing Cooling System Flushing.
- For cooling systems filled with Motorcraft(R) Specialty Orange Engine Coolant, a darker orange 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 Motorcraft(R) Specialty Orange Engine Coolant. Refer to Cooling System Flushing Cooling System Flushing.
- A light or reddish brown color or reddish brown particles indicate that rust may be present in the cooling system. Flush the system and refill with the correct mixture of distilled water and the correct engine coolant.
- 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 Engine System - General Information Testing and Inspection.
- A milky brown color may indicate that engine oil is entering the cooling system. Pressure test the cooling system. Refer to Component Tests. Component Tests and General Diagnostics If engine oil is suspected, the cause of the leak may be internal to the engine. Refer to Engine System - General Information Testing and Inspection.
2. If the engine coolant appearance is acceptable, test the engine coolant freezing point range with the Coolant/Battery Refractometer. The freezing point should be in the range -45°C to -23°C (-49°F to -9°F). If the vehicle is driven in cold climates less than -36°C (-33°F), it may be necessary to increase the coolant concentration to get adequate freeze protection. Recommended coolant concentration is 50/50 ethylene glycol to distilled water.
- Maximum coolant concentration is 60/40 for cold weather areas.
- Minimum coolant concentration is 40/60 for warm weather areas.
3. 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 next step.
10. NOTE: Make sure to use the latest scan tool software release.
If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).
11. NOTE: The Vehicle Communication Module (VCM) LED prove out confirms power and ground from the DLC are provided to the VCM.
If the scan tool does not communicate with the VCM:
- check the VCM connection to the vehicle.
- check the scan tool connection to the VCM.
- refer to Module Communications Network Testing and Inspection, No Power To The Scan Tool, to diagnose no power to the scan tool.
12. If the scan tool does not communicate with the vehicle:
- verify the ignition key is in the ON position.
- verify the scan tool operation with a known good vehicle.
- refer to Module Communications Network Testing and Inspection to diagnose no response from the PCM.
13. Carry out the network test.
- If the scan tool responds with no communication for one or more modules, refer to Module Communications Network Testing and Inspection.
- If the network test passes, retrieve and record Continuous Memory Diagnostic Trouble Codes (CMDTCs).
14. Clear the CMDTCs and carry out the self-test diagnostics for the PCM.
15. If the DTCs recovered are related to the concern, go to the PCM DTC Chart. For all other PCM DTCs, refer to Electronic Engine Controls - Hybrid Testing and Inspection. Diagnostic Trouble Code Tests and Associated Procedures
16. If no DTCs related to the concern are retrieved, GO to Symptom Chart. Symptom Related Diagnostic Procedures