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Frelander 2. Manual - part 228

Item

Part Number

Description

Engine

Thermostat

Cabin heater core

By-pass

Radiator

Venturi exit

Transmission oil cooler

Coolant pump

Coolant expansion tank

Engine oil cooler

PRINCIPLES OF OPERATION

At idle, and low outdoor temperatures (lower than -10°C (14°F)) the engine's idle speed increases from approximately 650
rpm to approximately 750 rpm. This is to increase the coolant flow through the passenger compartment element, which, in
turn, makes it possible to increase the heat in the passenger compartment. The coolant pump is driven by the power
steering pump through a flange.

Coolant Flow - Closed Thermostat

Coolant leaves the engine block via the 2 circuits at the rear edge on the intake side of the engine.

The coolant is routed from one of the circuits to the engine's oil cooler and onwards to the coolant pump.
Coolant is routed from the other circuit to a 'by-pass' circuit where there is a valve. The valve is closed at engine
speeds up to approximately 1500 rpm. At approximately 1500 rpm, the valve opens and coolant passes through the
circuit. By keeping the valve closed at low engine speeds, a sufficient flow is guaranteed through the passenger
compartment element to obtain a good climate (sufficient heat) in the passenger compartment.

Coolant Flow - Open Thermostat

When the thermostat opens, coolant is also routed to the radiator
The radiator has an inlet on the Right Hand (RH) side and 2 outlets on the left-hand side
The greater volume of cooled coolant is routed at the radiator's lower outlet to the coolant pump
At the upper outlet some of the coolant is routed to the automatic transmission's oil cooler. Before the coolant
reaches the oil cooler, it passes a 'choke' circuit through the radiator with a lower (slower) flow than other coolants.
This provides optimum cooling of the coolant before it reaches the oil cooler, which in turn, provides effective
cooling of the transmission oil. The coolant is routed from the oil cooler onwards to the coolant pump.

Bleeding

The engine has 2 bleed circuits connected to the expansion tank. One is located on the radiator and the other on the
cylinder head.

Radiator and Cooling Fan(s)

The radiator, which dissipates heat from the engine coolant and engine mounted oil cooler, is manufactured from a 27 mm
aluminum matrix with high-pressure injection molded end tanks.

Item

Part Number

Description

Cold to mild climate radiator

Hot climate radiator

Dependant on climate conditions there are 2 specifications of radiator fan available:

Cold to mild climates: a single fan unit designed around a 500W motor
Hot climates: a twin fan unit features two motors delivering a total of 750W

Common to both fan types are:

Electric motors with brushes
The Engine Control Module (ECM) controls the fan speed via Pulse Width Modulation (PWM) signals to the Electronic
Fan Control Module (EFCM)
The fan speed is controlled at 4 levels:

- Run-on occurs in 3 stages (i.e. depressing the fan speed)
- The engine cooling fan is activated a certain time after the engine has been switched off to protect various
engine components from overheating
- The time the fan is activated and the speed of the fan is dependent on the coolant temperature and the
driver's driving style (engine load) when the engine is switched off
- The hotter the engine and the hotter the load, the higher the fan speed and the longer run-on time. The

maximum time of run-on is 360 seconds

The EFCM can, by modulating the PW M control signal, inform the ECM about the fan's status and any faults.

PWM control of the fan motor provides variable control of fan speed to ensure minimum fan noise and reduced energy
consumption when fan operation is required. The control module is mounted above the wade water entry lines
For additional information, refer to:

Electronic Engine Controls

(303-14A Electronic Engine Controls - I6 3.2L Petrol,

Description and Operation).

The coolant expansion tank provides an expansion volume and permits easy in-service bleeding of the cooling system.
Coolant level sensing is precise to provide early warning in the event of low coolant level. To prevent intrusion into the
expansion tank's casing, which could be a potential leak path, a magnetic float within the tank activates a switch located
outside the tank.

Engine Cooling - I6 3.2L Petrol - Engine Cooling

Diagnosis and Testing

Principles of Operation

For a detailed description of the cooling system, refer to the relevant Description and Operation section in the workshop
manual.
REFER to:

Engine Cooling

(303-03A Engine Cooling - I6 3.2L Petrol, Description and Operation).

Inspection and Verification

CAUTION: Diagnosis by substitution from a donor vehicle is NOT acceptable. Substitution of control modules does

not guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor
vehicle.

1. Verify the customer concern.

2. Visually inspect for obvious signs of mechanical or electrical damage.

Visual Inspection

Mechanical

Electrical

Coolant leaks
Coolant expansion tank
Electric fan
Radiator

Fuse
Wiring harness
Loose or corroded connector(s)
Engine Coolant Temperature (ECT) sensor

3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before

proceeding to the next step

4. If the cause is not visually evident, verify the symptom and refer to the Symptom Chart, alternatively, check for

Diagnostic Trouble Codes (DTCs) and refer to the DTC Index.

Symptom Chart

Symptom

Possible Cause

Action

Coolant loss

Hoses
Hose connections
Radiator
Coolant pump
Heater core
Gaskets
Engine casting cracks
Engine block core plugs

GO to Pinpoint Test

Engine overheating

Engine coolant (level/condition)
Thermostat
Fan motor
Fan motor fuses and/or circuits
ECT sensor
Engine control module (ECM)
Fan speed module

GO to Pinpoint Test

Engine not reaching normal operating temperature

Thermostat
Electric fan
Fan speed module

GO to Pinpoint Test

DTC Index

• NOTE: If the control module or a component is suspect and the vehicle remains under manufacturer warranty, refer to the
Warranty Policy and Procedures manual (section B1.2), or determine if any prior approval programme is in operation, prior
to the installation of a new module/component.

• NOTE: Generic scan tools may not read the codes listed, or may read only five digit codes. Match the five digits from the
scan tool to the first five digits of the seven digit code listed to identify the fault (the last two digits give extra
information read by the manufacturer approved diagnostic system).

• NOTE: When performing voltage or resistance tests, always use a digital multimeter (DMM) accurate to three decimal
places, and with a current calibration certificate. When testing resistance, always take the resistance of the DMM leads
into account.

• NOTE: Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.

• NOTE: If DTCs are recorded and, after performing the pinpoint tests, a fault is not present, an intermittent concern may
be the cause. Always check for loose connections and corroded terminals.

DTC

Description

Possible Cause

Action

P011600 Engine coolant temperature sensor 1

circuit range/performance

Engine coolant temperature
(ECT) sensor 1 circuit: high

Check the ECT sensor and circuits.
Refer to the electrical guides. Install a

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