Engine Cooling: Other Ford Focus II

Fail Safe Cooling

The vehicle has a strategy built into the powertrain control module (PCM) that will control the engine if it starts to overheat.

Stage 1 of the strategy will commence if the engine starts to overheat. The cylinder head temperature (CHT) sensor transmits a signal to the PCM, which then moves the temperature gauge pointer into the red zone.

If the engine is not switched off and the temperature continues to rise, the Powertrain Check Lamp is illuminated. This indicates to the driver that the engine is approaching critical limits and should be stopped. At this point DTC P1285 is set in the PCM which can be retrieved using a diagnostic tool.

Stage 2 of the strategy will commence if the lamp and temperature gauge are ignored by the driver. The PCM will start to control the engine by cutting out 2 cylinders and restricting the RPM to below 3,000 RPM. Simultaneously the malfunction indicator lamp (MIL) will be illuminated. This indicates that long term engine damage can occur and vehicle emissions will be affected. At this point DTC P1299 is set in the PCM which can be retrieved using a diagnostic tool.

Air is then drawn into the deactivated cylinders. This helps to control the temperature of the engine internal components. The deactivated cylinders are alternated to allow even cooling of all the cylinders.

Note. If the driver is using a high percentage of throttle travel (for example, an overtaking maneuver) when the PCM starts engine deactivation (Stage 2), the deactivation will be delayed for 10 seconds.

Note. After 2-cylinder operation has begun, the engine will not revert to 4-cylinder operation, even if the temperature should fall, until the ignition is switched off and then on again.

Note. The malfunction indicator lamp can only be extinguished by using a diagnostic tool after the fault has been rectified and the DTC cleared.

Stage 3 of the strategy will commence if the engine temperature still continues to rise. This will result in the engine being totally disabled before major engine damage or seizure occurs. The Powertrain Check Lamp will begin to flash, indicating to the driver that the engine will be switched off after 30 seconds. This allows the driver time to choose a suitable parking place.

Materials

MATERIALS

Cap

1. Inspect the pressure relief cap and seals for damage or deterioration. Install a new pressure relief cap if necessary.
2. Fit the pressure relief cap to the Radiator/Heater Core Pressure Tester Kit using the correct adapter.
3. Slowly pump the pressure tester until the pressure gauge stops increasing and note the highest pressure reading. Release the pressure and repeat the test. Install a new pressure relief cap if the pressure is not within specification. Refer to the «GENERAL SPECIFICATIONS»(ref-255386-S24388191372007080900000) in this article.

Thermostat

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

1. Pinpoint Test A, B or C
2. Thermostat Visual Inspection

MATERIALS

Scheme 16

Scheme 17

1. Release the cooling system pressure by slowly turning the pressure relief cap a quarter of a turn.
2. Remove the pressure relief cap when all the pressure has been released.
3. With the vehicle in NEUTRAL, position it on a hoist. For additional information, refer to «JACKING AND LIFTING»(ref-255374) .
4. Remove the retainers and the engine undershield.
5. Open the radiator drain valve to drain the coolant.
6. Close the drain valve when all the coolant has been drained from the system.
7. Install the retainers and the engine under shield.

Filling and Bleeding with RADKITPLUS

1. Using the special tool, install the RADKITPLUS and follow the manufacturer's instructions to fill and bleed the cooling system.

Filling and Bleeding without RADKITPLUS

Note. The addition of Cooling System Stop Leak Pellets darkens Motorcraft Premium Gold Engine Coolant from yellow to golden tan.

Scheme 18

1. Fill the degas bottle to 15 mm (0.60 in) above the max level mark (with the engine switched off).
2. Install the degas bottle cap.
3. Start the engine, run and hold at 2500 RPM for approximately 8 minutes until the thermostat opens, then for another 3 minutes after the thermostat opens.
4. Increase the engine speed briefly to 4000 RPM and hold for approximately 5 seconds.
5. Return the engine speed to 2500 RPM and hold for another 3 minutes.
6. Stop the engine and check for any leaks.

Thermostat Housing

MATERIALS

Scheme 19

Scheme 20

Scheme 21

Scheme 22

Scheme 23

1. With the vehicle in NEUTRAL, position it on a hoist. For additional information, refer to «JACKING AND LIFTING»(ref-255374) .
2. Drain the cooling system. For additional information, refer to «COOLING SYSTEM DRAINING, FILLING AND BLEEDING»(ref-255386-S35525310252007053100000) in this article.
3. Remove the 2 bolts and the accessory drive belt splash shield. To install, tighten to 9 Nm (80 lb-in).
4. Using the pulley bolt, rotate the accessory drive belt tensioner clockwise and remove the accessory drive belt from the A/C compressor.
5. Using the hex feature, rotate the accessory drive belt tensioner clockwise and remove the accessory drive belt from the A/C compressor.
6. Remove the 2 nuts and position aside the power steering tube. To install, tighten to 10 Nm (89 lb-in).
7. Remove the cooling fan motor and shroud. For additional information, refer to «COOLING FAN MOTOR AND SHROUD»(ref-255386-S17481682062007053100000) in this article.
8. Remove the 2 bolts, the stud bolt and position aside the A/C compressor. To install, tighten to 25 Nm (18 lb-ft).
9. Release the spring-style clamps and disconnect the radiator and heater hoses from the thermostat housing.
10. Remove the 3 bolts, thermostat housing and thermostat as an assembly. To install, tighten to 10 Nm (89 lb-in).
11. To install, reverse the removal procedure.
12. Fill and bleed the cooling system. For additional information, refer to «COOLING SYSTEM DRAINING, FILLING AND BLEEDING»(ref-255386-S35525310252007053100000) in this article.

Coolant Pump

MATERIALS

Scheme 24