SSANGYONG TURISMO 2013 Service Manual

10-4
1. OVERVIEW
The pre-heating system for D20DTR engine has the glow plug to the cylinder head (combustion
chamber), and improves the cold start performance and reduces the emission level.
The pre-heating resistor (air heater) is used to heat the intake air.
This enables the diesel fuel to be ignited in low temperature condition.
The ECU receives the information such as, engine rpm, coolant temperature, engine torque, etc.,
through CAN communication during pre-heating process; and the pre-heating control unit controls the
pre-heating, heating during cranking and post-heating by the PWM control.
Glow plug
Engine ECU (D20DTR)Glow indicator
Glow plug control unit
(GCU)

10-51413-00
2. SYSTEM OPERATION
1) Input/Output Diagram of Glow Plug Control Unit
2) System Diagram

10-6
3) Circuit Diagram

10-71413-00
4) Operation
Glow plug is installed in the cylinder head. It enhances the cold starting performance and reduces the
exhaust gas during cold starting.
ECU receives the data (engine rpm, coolant temperature, vehicle speed) through CAN lines. Based on
the data, GCU controls the pre-glow, cranking and post-glow. It also checks the glow plugs, and sends
the result to ECU.
(1) Temperature/Current Properties of GCU
GCU increases the temperature of glow plug very rapidly (approx. 2 seconds up to
1000°C)
FETs (similar to transistor) for each cylinder are integrated in GCU. During the pre-glow
period, battery voltage is supplied to the glow plugs directly to heat them rapidly.
After getting the desired temperature by pre-glowing, the temperature is controlled by duty
ratio. Step 1:
Step 2 & 3:
Step 4:
This shows the supplying voltage and time by GCU in each step. The step 4 is the period to keep
the temperature. -Step 1: I1
Step 2: I2
Step 3: I3
Step 4: I4

10-8
(2) Pre-heating time control based on battery voltage
GCU monitors the battery voltage. If it is low, GCU extends the pre-heating time.
GCU monitors the energy to glow plugs (the amount of pre-heating energy is always same). -
-
GCU monitors the battery voltage. If it is low, GCU extends the pre-heating time to get enough
energy. -
GCU monitors the battery voltage. If it is low, GCU increases PWM duty.. -

10-91413-00
(3) Power control
GCU PWM control
This describes the voltage supplying types to glow plugs. -
GCU estimates the temperature of glow plug for pre-heating. To avoid the power loss and overheat,
GCU supplies the lowest power for getting target temperature when turning ON the ignition from
OFF. -
(4) Operation
Frequency: 20~33Hz
PWM control duty ratio
- 1st step: 100%
- 2~3 step: 35%
- 4th step: 23%

10-10
(5) Pre-glow and Post-glow
This shows the pre-glow and post-glow step as a chart.

11-31461-01
1. SPECIFICATION
Description Specification
Capacity 12V 2.3kW
Engagement Meshed type
Rotating direction Clockwise
Pinion gear manufacturing Cooled forging
Solenoid operating voltage Max. 8 V
Weight 2.5 kg
Bracket manufacturing Aluminum die casting

11-4
2. TROUBLESHOOTING
Problem Possible Cause Action
Engine will not crankLow battery voltage Charge or replace
Loose, corroded or damaged battery cable
Repair or replace
Faulty starter or open circuit
Faulty ignition switch or blown fuseRepair or replace
Poor engine ground Repair
Engine cranks too
slowLow battery voltage Charge or replac
Loose, corroded or damaged battery cable
Repair or replace Faulty starter
Starter does not
stopFaulty starter
Faulty ignition switch Replace
Engine cranks
normally, but does
not startBroken pinion gear or faulty starter
Replace the starter
Broken flywheel ring gear Replace
Open circuit Repair

11-51461-01
1. SYSTEM DESCRIPTION
The starter (start motor) starts the engine with rotational power by converting the electric energy to the
mechanical energy.
When the engine is cranking, the pinion gear meshes with the ring gear. If the ring gear overruns, the
pinion gear clutch overruns to protect the pinion gear.
2. OPERATING PROCESS
1) System Layout