Charging System
Components and Component Location
Components
① ECU
② Battery
③ Generator
④ Starter
⑤ Instrument cluster
⑥ Ignition switch or Start/Stop button
⑦ Battery sensor
⑧ Hood switch
Description and Operation
Description
The charging system consists of the battery, the generator with built-in regulator, the charge warning light, and wiring.
The AC generator has eight built-in diodes, each of which converts alternating current to direct current.
Therefore, direct current appears at the generator "B" terminal.
In addition, the charging voltage of this generator is controlled by the battery voltage sensing system.
The generator is controlled by the battery voltage sensing system. The main components of the generator are the rotor, stator, rectifier, capacitor, brushes, bearings, and pulley with poly-V belt. The brush holder contains a built-in electronic voltage regulator.
Generator Control System
The generator control system adjusts the charging voltage setpoint to improve fuel economy, manage generator load under various operating conditions, keep the battery charged, and protect the battery from overcharging. The engine control module controls generator voltage by duty cycle (charge control, discharge control, normal control) depending on battery condition and vehicle operating conditions.
The system performs discharge control during vehicle acceleration. The vehicle reduces generator load and draws electrical power from the battery.
The system performs charge control during vehicle deceleration. The vehicle increases generator load and charges the battery.
Circuit Diagrams
Wiring Diagram
Repair Procedures
Inspection
Inspection Item
Battery Performance Check
Battery Voltage Check
Charging Voltage Check
General Inspection
Terminal Tightness Check
Engine / Transmission Condition Check
Wiring Harness Ground Condition Check
Specified Electrical Value Check
Vehicle Parasitic Current Check
Battery Capacity Check
Battery Efficiency Inspection
Battery Voltage Check
After driving the vehicle, if 20 minutes have not elapsed after engine shutdown, turn the ignition on and operate electrical loads (headlights, blower motor, rear window defroster, etc.) for 60 seconds to remove the surface charge.
Turn the ignition OFF and turn off the electrical systems.
Measure the battery voltage between the battery negative (-) and positive (+) terminals.
Standard voltage: Approximately 12.5 - 12.9 V [20 °C]
If the voltage is below the specified value, charge the battery.
General Inspection
Make sure the battery terminals are not loose or corroded.
(Refer to Charging System - "Battery")
Check the fuses for continuity.
Generator Fuse
Check the generator fuse (A) for continuity.
Measure the voltage as shown in the illustration below.
Standard value: Approximately 0 V
If the alternator fuse is blown, replace it according to the procedure below:
a. Turn the ignition off and disconnect the negative (-) battery terminal.
b. Remove the nuts securing the positive (+) battery cable.
b. Replace the regular alternator fuse or the battery cable.
d. Install in the reverse order of removal.
Battery Sensor Fuse
Check the battery sensor fuse for continuity.
Replace with a standard battery sensor fuse.
Measure the voltage.
Standard value: Approximately 0 V
Inspect the drive belt
Visually inspect the belt for excessive wear, frayed cords, etc.
If any defect is found, replace the drive belt.
Measure and adjust the drive belt tension.
(Refer to Engine Mechanical System - "Drive Belt")
Visually inspect the alternator wiring and listen for abnormal noise.
Make sure the wiring is in good condition.
Make sure there is no abnormal noise from the generator while the engine is running.
Check the charge warning lamp circuit.
Warm up the engine, then turn it off.
Turn off all accessories.
Turn the ignition switch ON. Make sure the charge warning light illuminates.
Start the engine. Check that the warning light illuminates.
If the light does not turn off as specified, repair the charge warning light circuit.
Terminal Tightening Inspection
Location of check component
| 1. Alternator B+ terminal 2. Engine compartment fuse and relay block positive (+) terminal 3. Battery positive (+) terminal |
4. Battery negative (-) terminal 5. Body ground |
Engine/Transaxle Inspection
Wire Harness Ground Inspection
| 1. Engine ground (engine ↔ body) 2. Transmission ground (transmission ↔ body) |
Electrical Specifications Value Check (Using Voltmeter and Ammeter)
Generator Output Wire Voltage Drop Test
This test determines whether the wiring between the generator "B" terminal and the battery (+) terminal is in good condition using the voltage drop method.
Preparation
a. Turn the ignition switch to the OFF position.
b. Disconnect the output wire from the generator "B" terminal. Connect the (+) lead of the ammeter to the generator "B" terminal and the (-) lead of the ammeter to the output wire. Connect the (+) lead of the voltmeter to the generator "B" terminal and the (-) lead of the voltmeter to the battery (+) terminal.
Test
a. Start the engine.
b. Turn on the headlights and blower motor, adjust the engine speed until the ammeter shows 20 A, and read the voltmeter.
Result
a. The voltmeter may show the standard value.
Standard value: 0.2 V max.
b. If the voltmeter reading is higher than expected (more than 0.2 V maximum), suspect a wiring fault. In this case, inspect the wiring from the generator "B" terminal to the battery (+) terminal. Check for loose connections, discoloration due to harness overheating, etc. Repair them before retesting.
b. After the inspection is completed, set the engine speed to idle. Turn off the headlights, blower motor and ignition switch.
Output Current Test
This test determines whether the generator produces output current equivalent to normal output.
Preparation
a. Before testing, check the following items and correct as necessary.
Check the battery installed in the vehicle to make sure it is in good condition. Refer to "Battery" for battery inspection.
The battery used for the output current test must be partially discharged.
If the battery is fully charged, the test may not be performed correctly due to insufficient load.
Check the generator drive belt tension. Refer to "Inspect Drive Belt" for belt tension inspection.
b. Turn the ignition off.
b. Disconnect the battery ground cable.
d. Disconnect the generator output wire from generator terminal "B".
e. Connect a DC ammeter (0 to 150 A) in series between the generator "B" terminal and the disconnected output wire. Be sure to connect the (-) lead of the ammeter to the disconnected output wire.
f. Connect a voltmeter (0 to 20 V) between generator terminal "B" and ground. Connect the voltmeter (+) lead to generator terminal "B" and the (-) lead to ground.
g. Connect the battery ground cable.
h. Leave the engine hood open.
Test
a. Make sure the voltmeter shows the same value as the battery voltage. If the voltmeter shows 0 V, there is an open circuit in the wire between generator terminal "B" and the battery (+) terminal, or a poor ground connection.
b. Start the engine and turn on the headlights.
b. Turn the headlights to high beam and the blower fan switch to HIGH. Quickly increase engine speed to 2500 rpm and read the maximum output current value on the ammeter.
Result
a. The ammeter reading must be above the specified limit. If it is below, even though the generator output wire is in good condition, remove the generator from the vehicle and inspect it.
Limit value: 60% of the current rating
b. After completing the output current test, reduce the engine speed to idle and turn the ignition switch OFF.
b. Disconnect the negative (-) battery terminal.
d. Remove the ammeter, voltmeter and engine tachometer.
e. Connect the generator output wire to the generator B terminal.
f. Connect the negative (-) battery terminal.
Regulated Voltage Test
The purpose of this test is to check that the electronic voltage regulator correctly regulates voltage.
Preparation
a. Before testing, check the following items and correct if necessary.
Make sure the battery installed in the vehicle is fully charged. Refer to "Battery" for battery inspection.
Check the generator drive belt tension. Refer to "Inspect Drive Belt" for belt tension inspection.
b. Turn the ignition switch to the OFF position.
b. Disconnect the negative (-) battery terminal.
d. Connect a digital voltmeter between the generator "B" terminal and ground. Connect the voltmeter (+) lead to the generator "B" terminal. Connect the voltmeter (-) lead to a good ground or to the battery (-) terminal.
e. Disconnect the generator output wire from generator terminal "B".
f. Connect a DC ammeter (0 to 150 A) in series between the "B" terminal and the disconnected output wire. Connect the ammeter (-) lead to the disconnected output wire.
g. Connect the negative (-) battery terminal.
Test
a. Turn the ignition switch ON and check that the voltmeter shows the following value.
Voltage: Battery voltage
If it indicates 0 V, there is an open circuit in the wire between the generator "B" terminal and the battery, or in the battery (-) terminal connection.
b. Start the engine. Turn off all lights and accessories.
b. Run the engine at approximately 2500 rpm and read the voltmeter when the generator output current drops to 10 A or less.
Result
a. If the voltmeter reading does not meet the standard value, the voltage regulator or the generator is faulty.
Regulated voltage: 11.7–15.3 V
b. If the voltmeter reading does not meet the standard value, the voltage regulator or the generator is faulty.
b. Disconnect the negative (-) battery terminal.
d. Remove the voltmeter and ammeter.
e. Connect the generator output wire to the generator B terminal.
f. Connect the negative (-) battery terminal.
Electrical Specifications Value Check (Using Voltmeter and Clamp-Type Ammeter)
Generator Output Wire Voltage Drop Test
This test determines whether the wiring between the generator "B" terminal and the battery (+) terminal is in good condition using the voltage drop method.
Preparation
a. Turn the ignition switch to the OFF position.
b. Install a clamp-type ammeter around the positive (+) wire between the battery and the generator B terminal.
b. Connect the voltmeter (+) lead to the generator "B" terminal and the voltmeter (-) lead to the battery (+) terminal.
Test
a. Start the engine.
b. Turn on the headlights and blower motor, adjust the engine speed until the ammeter shows 20 A, and read the voltmeter.
Result
a. The voltmeter may show the standard value.
Standard value: 0.2 V max.
b. If the voltmeter reading is higher than expected (more than 0.2 V maximum), suspect a wiring fault. In this case, inspect the wiring from the generator "B" terminal to the battery (+) terminal. Check for loose connections, discoloration due to harness overheating, etc. Repair them before retesting.
b. After the inspection is completed, set the engine speed to idle. Turn off the headlights, blower motor and ignition switch.
Output Current Test
This test determines whether the generator produces output current equivalent to normal output.
Preparation
a. Before testing, check the following items and correct as necessary.
Check the battery installed in the vehicle to make sure it is in good condition. Refer to "Battery" for battery inspection.
The battery used for the output current test must be partially discharged.
If the battery is fully charged, the test may not be performed correctly due to insufficient load.
Check the generator drive belt tension. Refer to "Inspect Drive Belt" for belt tension inspection.
b. Turn the ignition off.
b. Disconnect the negative (-) battery terminal.
d. Install a clamp-type ammeter around the positive (+) wire between the battery and the generator B terminal.
e. Connect a DC ammeter (0 to 150 A) in series between the generator "B" terminal and the disconnected output wire. Be sure to connect the (-) lead of the ammeter to the disconnected output wire.
f. Connect a voltmeter (0 to 20 V) between generator terminal "B" and ground. Connect the voltmeter (+) lead to generator terminal "B" and the (-) lead to ground.
g. Connect the negative (-) battery terminal.
h. Leave the engine hood open.
Test
a. Make sure the voltmeter shows the same value as the battery voltage. If the voltmeter shows 0 V, there is an open circuit in the wire between generator terminal "B" and the battery (+) terminal, or a poor ground connection.
b. Start the engine and turn on the headlights.
b. Turn the headlights to high beam and the blower fan switch to HIGH. Quickly increase engine speed to 2500 rpm and read the maximum output current value on the ammeter.
Result
a. The ammeter reading must be above the specified limit. If it is below, even though the generator output wire is in good condition, remove the generator from the vehicle and inspect it.
Limit value: 60% of the voltage standard
b. After completing the output current test, reduce the engine speed to idle and turn the ignition switch OFF.
b. Disconnect the negative (-) battery terminal.
d. Remove the ammeter, voltmeter and engine tachometer.
e. Connect the generator output wire to the generator B terminal.
f. Connect the negative (-) battery terminal.
Regulated Voltage Test
The purpose of this test is to check that the electronic voltage regulator correctly regulates voltage.
Preparation
a. Before testing, check the following items and correct if necessary.
Make sure the battery installed in the vehicle is fully charged. Refer to "Battery" for battery inspection.
Check the generator drive belt tension. Refer to "Inspect Drive Belt" for belt tension inspection.
b. Turn the ignition switch to the OFF position.
b. Disconnect the negative (-) battery terminal.
d. Connect a digital voltmeter between the generator "B" terminal and ground. Connect the voltmeter (+) lead to the generator "B" terminal. Connect the voltmeter (-) lead to a good ground or to the battery (-) terminal.
e. Disconnect the generator output wire from generator terminal "B".
f. Connect a DC ammeter (0 to 150 A) in series between the "B" terminal and the disconnected output wire. Connect the (-) lead of the ammeter to the disconnected output wire.
g. Connect the negative (-) battery terminal.
Test
a. Turn the ignition switch ON and check that the voltmeter shows the following value.
Voltage: Battery voltage
If it indicates 0 V, there is an open circuit in the wire between the generator "B" terminal and the battery, or in the battery (-) terminal connection.
b. Start the engine. Turn off all lights and accessories.
b. Run the engine at approximately 2500 rpm and read the voltmeter when the generator output current drops to 10 A or less.
Result
a. If the voltmeter reading does not meet the standard value, the voltage regulator or the generator is faulty.
Regulated voltage: 11.7–15.3 V
b. If the voltmeter reading does not meet the standard value, the voltage regulator or the generator is faulty.
b. Disconnect the negative (-) battery terminal.
d. Remove the voltmeter and ammeter.
e. Connect the generator output wire to the generator B terminal.
f. Connect the negative (-) battery terminal.
Vehicle Parasitic Current Inspection
[Using an Ammeter]
Turn off all electrical devices, then turn the ignition OFF.
Close all doors except the hood, then lock all doors.
Disconnect the hood switch connector.
Close the liftgate.
Close the doors or remove the door switches.
Wait several minutes until the vehicle's electrical systems enter sleep mode.
Connect the ammeter in series between the negative (-) battery terminal and the ground cable, then slowly disconnect the clamp from the negative (-) battery terminal.
Read the ammeter current value.
If the parasitic current exceeds the limit value, search for the abnormal circuit by removing the fuses one at a time and checking the parasitic current.
Install only the fuse suspected of parasitic current and search for the faulty unit by disconnecting the components connected to the circuit one at a time until the parasitic draw drops below the limit value.
Limit value (after 10-20 min.): Less than 50 mA
[Using a Clamp-Type Ammeter]
Turn off all electrical devices, then turn the ignition OFF.
Close all doors except the hood, then lock all doors.
Disconnect the hood switch connector.
Close the liftgate.
Close the doors or remove the door switches.
Wait several minutes until the vehicle's electrical systems enter sleep mode.
Install the clamp-type ammeter on the negative (-) battery terminal.
Read the ammeter current value.
If the parasitic current exceeds the limit value, search for the abnormal circuit by removing the fuses one at a time and checking the parasitic current.
Install only the fuse suspected of parasitic current and search for the faulty unit by disconnecting the components connected to the circuit one at a time until the parasitic draw drops below the limit value.
Limit value (after 10-20 min.): Less than 50 mA
Troubleshooting
Troubleshooting
| Symptom | Suspected Area | Remedy |
| The charge warning lamp does not illuminate during IG ON. | Generator main fuse blown | Inspect/repair/replace the fuse. |
| Instrument cluster fuse blown | Inspect/repair/replace the fuse. | |
| Instrument cluster internal lamp broken | Inspect/repair/replace the instrument cluster. | |
| Faulty wiring connector connection | Inspect/repair/replace the wiring connection. | |
| Faulty voltage regulator or alternator | Inspect/repair/replace the voltage regulator or alternator. | |
| Incorrect battery terminal connection | Check the tightening torque of the battery (+) and (-) terminals to the specified torque. | |
| Communication Error | Inspect the wiring between the regulator and ECM. | |
| Check the ECM transmission signal. | ||
| Inspect/repair/replace the alternator if the wiring and ECM are normal. | ||
| Charging warning lamp does not turn off with the engine running. | Worn drive belt or lack of belt tension | Inspect/repair/replace the drive belt. |
| Poor connection, rusted or worn battery cable | Inspect the battery cable connection and check/repair/replace the cable. | |
| Generator main fuse blown | Inspect/replace the alternator main fuse or the battery cable. | |
| Faulty voltage regulator or alternator | Inspect/replace the voltage regulator or alternator. | |
| Faulty wiring | Inspect/replace the wiring. | |
| Faulty instrument cluster | Inspect/replace the instrument cluster. | |
| Alternator pulley slipping | Inspect/replace the alternator pulley. | |
| Adjust the tension / replace the drive belt. | ||
| Incorrect battery terminal connection | Check the tightening torque of the battery (+) and (-) terminals to the specified torque. | |
| The charging warning lamp illuminates. | Drive belt slipping, worn, or insufficient tension | Adjust the tension / replace the drive belt. |
| Inspect/replace the automatic tensioner (for automatic tensioner type only). | ||
| Alternator Management System (AMS) voltage error | Inspect the battery sensor harness and its body ground connection. | |
| Battery sensor error. | Inspect/repair/replace the battery sensor. | |
| Short circuit between the battery sensor wiring and body | Inspect/repair/replace the battery sensor. | |
| Output of terminal L of faulty alternator | Inspect/repair/replace the alternator or regulator. | |
| Degradation due to poor battery (+) terminal contact | Check the tightening torque to the specified torque / Inspect / Repair / Replace the battery wiring. | |
| Short circuit in the internal contact of the alternator extension connector | Inspect/repair/replace the wiring. | |
| Short circuit between the body and ground | Inspect/repair/replace the ground. | |
| Communication Error | Inspect/repair/replace the wiring between the regulator and ECM. | |
| Check the ECM transmission signal. | ||
| Inspect/repair/replace the alternator if the wiring and ECM are normal. | ||
| Short circuit in the middle of the connection to the alternator L terminal (Vehicle model with L terminal) |
Inspect/repair/replace the wiring. | |
| Rotation of the drive belt stops due to slipping of the crankshaft damper pulley or a faulty pulley. | Inspect or replace the crankshaft damper pulley / Inspect, repair or replace the drive belt tensioner bearing. | |
| Drive belt slipping, worn, or insufficient tension | Adjust the tension / inspect / repair / replace the drive belt. | |
| Faulty voltage regulator | Inspect/repair/replace the voltage regulator. | |
| Faulty alternator | Inspect/repair/replace the alternator. | |
| Generator main fuse blown | Inspect/repair/replace the alternator main fuse or the battery wiring. | |
| Defective ground | Inspect/repair/replace the ground. | |
| Discharged battery | Adjust the tension / inspect / repair / replace the drive belt. | |
| Inspect/repair/replace the wiring connection. | ||
| Inspect/repair/replace the alternator main fuse. | ||
| Inspect/repair/replace the alternator. | ||
| Inspect/repair/replace the voltage regulator. | ||
| Inspect/repair/replace the battery assembly. | ||
| Check for parasitic current draw / repair / replace. | ||
| Learn/inspect/repair/replace the battery sensor. | ||
| Check for short circuit / repair / replace the battery cable. | ||
| Inspect/repair/replace the ECM. | ||
| Inspect/repair/replace the body electrical parts. | ||
| Check/repair/replace the installation condition of the alternator connector. | ||
| Inspect/repair/replace the battery (+) and (-) terminal tightening to the specified torque. | ||
| Swollen battery | Faulty battery | Inspect/replace the battery. |
| Faulty voltage regulator or alternator | Inspect/repair/replace the voltage regulator or alternator. | |
| Faulty parts or wiring related to charging | Inspect / repair / replace the parts and wiring related to charging. | |
| After inspection, repair or replace the relevant parts if faulty. | ||
Test yourself
A quick Kia Stinger CK quiz: every answer comes with an explanation and a link to the manual page.