Kia Optima Hybrid: Engine Electrical System / Troubleshooting

Trouble Shooting
Ignition System
Symptom
Suspect area
Remedy
Vehicle indicates Ready in dash, but engine will not run when requested by the HPCU (HEV module).
Ignition coil
Inspect ignition coil, or replace as required
Spark plugs
Inspect spark plugs, or replace as required
Ignition wiring disconnected or broken
Repair wiring, or replace as required
Rough idle
Ignition wiring
Repair wiring, or replace as required
Ignition coil
Inspect ignition coil, or replace as required
Engine hesitates/poor acceleration
Spark plugs and spark plug cables
Inspect spark plugs / cable, or replace as required
Ignition wiring
Repair wiring, or replace as required
Poor mileage
Spark plugs and spark plug cables
Inspect spark plugs / cable, or replace as required

Charging System
Symptom
Suspect area
Remedy
Charging warning indicator does not light with Start/Stop Button "ON" and Hybrid System off.
Fuse blown
Check fuses
Light burned out
Replace light
Wiring connection loose
Tighten loose connection
LDC problem
Check the LDC.
Refer to HC group
Charging warning indicator does not go out with Hybrid System on. (Battery requires frequent recharging)
Battery cable loose, corroded or worn
Inspect cable connection, repair or replace cable
LDC problem
Check the LDC.
Refer to HC group
Wiring
Repair or replace wiring
Overcharge
LDC problem
Check the LDC.
Refer to HC group
Voltage sensing wire
Repair or replace wiring
Discharge
Wiring connection loose or short circuit
Inspect wiring connection, repair or replace wiring
LDC problem
Check the LDC.
Refer to HC group
Poor grounding
Inspect ground or repair
Worn battery
Replace battery
Abnormal parasitic draw from the vehicle
Install a current probe to measure current. It should be less than 0.05A (50mA) after Hybrid System off and waiting 10 minutes. Make sure trunk light is removed for this test.

Starting System
Symptom
Suspect area
Remedy
Vehicle will not indicate Ready in dash at Hybrid System on.
Auxiliary 12V battery charge low
Charge or replace auxiliary 12V battery
Auxiliary 12V battery cables loose, corroded or worn out
Repair or replace cables
Transaxle range switch (Vehicle with automatic transaxle only)
Refer to AT group-automatic transaxle
Fuse blown
Replace fuse
Ignition switch faulty
Replace

Special Service Tools

Personal Protective Equipment NameIllustrationDescriptionInsulation gloveUsed when inspecting or working on the high voltage components[Insulation performance : 1000V / 300A or above]Insulation shoesUsed ...

Charging System

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Other information:

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: SS-B Solenoid Valve (ON/OFF) Repair procedures


Inspection 1. Turn ignition switch OFF. 2. Remove the air duct (A). Tightening torque: 7.8 ~ 9.8 N.m (0.8 ~ 1.0 kgf.m, 5.8 ~ 7.2 lb-ft) 3. Remove the air cleaner assembly. (1) Disconnect the breather hose (A). (2) Disconnect the air intake hose (B) and then remove the air cleaner assembly (C). Tightening ...

Kia Optima Hybrid (TF HEV) 2016-2020 Service Manual: Electric A/C compressor Specifications


Specification ModelESC33i MotroBLDC MotorControl TypeCANCompression TypeScrollCapacity33cc/revOperating Voltage Range190~320VRated Voltage288VMount TypeEngine Mounting, 6 Point Mounting ...

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