2012 SSANGYONG NEW REXTON engine

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2) Troubleshooting for Alternator
Item Cause Action
Overcharged batteryDefective alternator voltage regulator
Replace the alternator
Defective voltage detection wiring Repair or replace
Loose alternator drive belt Adjust the belt tension or replace
Discharged batteryPoor connection of related circuit or open
circuitRetighten the loose connection or
repair open circuit
Defective alternator voltage regulator
Replace the alternator
Defective alternator voltage regulator
Replace the alternator
Terminated battery Replace the battery
Defective ground Repair
Charge warning
lamp does not come
on when turning on
ignition switch with
engine stoppedDefective alternator voltage regulator
Replace the alternator
Open circuit in charge warning lamp, fuse
or wiringReplace or repair the charge warning
lamp or fuse
Defective ignition switch Replace the ignition switch
Defective ground of alternator circuit Repair
Charge warning
lamp is not turned
off after starting
engineDefective alternator voltage regulator
Replace the alternator
Corroded or worn battery cableRepair or replace the battery cable
Loose alternator drive belReplace the batteryAdjust the belt
tension or replace the belt
Defective wiring harness Repair or replace

(3) Starting with jumper cable
If the battery is weak or terminated, the battery from another vehicle can be used with jumper cables to
start the engine.
Connecting order
The positive (+) terminal of the discharged battery
The positive (+) terminal of the booster battery
The negative (-) terminal of the booster battery
Connect one end of the other jumper cable to the body of the discharged vehicle, such as the engine
block or a front towing hook. 1.
2.
3.
4.
Starting
Prepare a set of jumper cables.
Place another vehicle that has the same 12 V of power near to the discharged vehicle.
Switch off all electrical accessories for the discharged vehicle.
Apply the parking brake and shift the transaxle to the P position (automatic transaxle) or neutral (N)
position (manual transaxle).
Connect the jumper cables.
Try to start the discharged vehicle while accelerating the engine rpm in the booster vehicle.
Attempt to start the engine with the discharged battery.
After starting the engine, carefully disconnect the jumper cables in the reverse sequence of
connection. 1.
2.
3.
4.
5.
6.
7.
8.

Alternator
The alternator charges the battery and
supplies power to each electric unit by
converting the mechanical energy to the
electrical energy.
1. SYSTEM DESCRIPTION
1) Overview
The charge system is designed to supply electrical energy to the vehicle while driving, and supplies a
constant direct current voltage by converting mechanical rotational movement to electrical energy.
The voltage regulator on the back of the alternator controls the generated voltage in all rotating ranges
and adjusts the system voltage according to the electric load and ambient temperature change.
2) System Layout (Locations)
Battery
It converts the chemical energy to the
electrical energy and supplies power to the
corresponding electric units when starting the
engine.

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
Glow indicatorEngine ECU (D20DTR)
Glow plug control unit
(GCU)

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Voltage pattern in actual stepGCU PWM control
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.
Duty control area:
Between 5 and 100%
Frequency: 20 Hz
1.
2.
3.
(1) Temperature/Current Properties of GCU
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. 1.
2.
3.
Frequency:
20~33Hz
PWM control duty
ratio
- 1st step: 100%
- 2nd step: 35%
- 3rd step: 23%
This describes the voltage supplying types to glow plugs. This shows the supplying voltage and
time by GCU in each step. The 3rd
step is the period to keep the
temperature.
(2) Operation Type of GCU

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During cranking: Step 2 and step 3
Step 2: If the ECU receives the cranking signal after pre-heating (step 1), the GCU supplies the 1.
2.
Under fixed temperature: The AQGS unit supplies power for 30 seconds (Step 1 + Step 3)
if no cranking signal is received after the step 1.
At cranking: The step 3 is started after the step 2. *
*
Post-glow: Step 4:
The post-heating is for reducing HC/CO after the engine is started. If the time for post-heating exceeds
180 sec., the GCU unit cuts off the power to each glow plug even if there is pre-heating request from the
engine ECU.
Emergency glow
If no CAN signal is received for 4 seconds from the engine ECU after the IGN ON signal is input, the
GCU performs emergency preheat (Step 3) for 30 seconds.
Post-heatingOperating time
(approx.)
Operating time
(approx.)100 s 50 s 25 s 10 s 10 s

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Operation when there is no engine start signal (cranking) after ignition ON

2. TROUBLESHOOTING
ProblemAction
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 fuse Repair or replace
Poor engine ground Repair
Engine cranks too
slowLow battery voltage Charge or replace
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