Inspection and Verification
Inspection and VerificationWARNING: 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.
CAUTION: The engine cooling system is filled with Motorcraft Premium Gold Engine Coolant. Mixing coolant types degrades the corrosion protection of Motorcraft Premium Gold Engine Coolant.
NOTE: Vehicles equipped with a degas bottle system have the pressure relief cap on the degas bottle and no radiator cap. Vehicles equipped with a coolant expansion tank system have the pressure relief cap on the radiator.
1. Verify the customer concern.
2. Visually check the engine coolant level at the degas bottle or coolant expansion tank 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's concern by operating the engine to duplicate the condition.
6. NOTE: Refer to the coolant flow diagram under Description and Operation, Engine Cooling.
Inspect to determine if any of the following mechanical or electrical concerns apply.
Visual Inspection Chart
Visual Inspection Chart:
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. Inspect the coolant condition.
1 Inspect the coolant color.
- If Motorcraft 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 Battery/Anti-Freeze Tester. The freezing point should be in the range -45° C to -23° C (-50° F to -10° F). If the vehicle is driven in cold climates less than -36° C (-34° 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.
- A pale green color indicates incorrect coolant (green in color) may have been added to the system. Use of incorrect (green in color) coolant degrades the corrosion protection of Motorcraft Premium Gold Engine Coolant. Flush the system and refill with the correct mixture of distilled water and Motorcraft Premium Gold Engine Coolant.
- NOTE: If Cooling System Stop Leak Pellets are used, darkening of the Motorcraft Premium Gold Engine Coolant from yellow to golden tan will occur.
Dark brown could indicate a commercially available stop leak may have been used.
- 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 Motorcraft Premium Gold Engine Coolant.
- An iridescent sheen on top of the coolant could indicate a trace of oil is entering the system.
- A milky brown color may indicate that engine oil is entering the cooling system. Pressure test the cooling system. If engine oil is suspected, the cause of the leak may be internal to the engine.
- A red, orange or light green colored sheen on top of the coolant may indicate that transmission fluid is entering the cooling system. The cause may be a leaky radiator. Pressure test the cooling system.
- If the engine coolant is black (diesel only), the coolant level may have been low at a previous time. The exhaust gas recirculation (EGR) cooler may have failed and exhaust gas may be contaminating the coolant.
2 If the engine coolant appearance is acceptable, test the engine coolant freezing point range with the Battery/AntiFreeze Tester. The freezing point should be in the range -45° C to -23° C (-50° F to -10° F). If the vehicle is driven in cold climates less than -36° C (-34° 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 Information Bus (Module Communications Network) to diagnose no communication with 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 Information Bus (Module Configuration) 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 Information Bus (Multiplex Communications Network).
^ If the network test passes, retrieve and record continuous memory DTCs.
14. Clear the continuous DTCs 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 DTCs, refer to Body Control Systems (Multifunction Electronic Control Module). 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