Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Power/Display Defect
- System features/Misdiagnose cases
Inspection Description (1) System features - IGN ON (H/U B+, ACC Power on), H/U Power must be ON.
(Normal display - No lines, broken character, white screen)
- IGN OFF (B+, ACC Power off), H/U Power must be OFF
(No power on/off by itself)
(2) Misdiagnose cases - Vehicle modification affects multimedia (Black box, custom navigation, custom mic)
- Battery is drained
- Multimedia switch is OFF on fuse box
- IGN ON (H/U B+, ACC Power on), H/U Power must be ON.
- No power on
Inspection Description (1) Duplicate issue - Duplicate issue during IGN ON (BATT, ACC Power on) is it intermittent?
→ If unable to duplicate, proceed with test driving
(2) External/Environmental issue - Vehicle modification
- Cable connection
- Vehicle modification
- Custom Navigation installed/black box power on/Reception related modification
- Fuse box - Multimedia Fuse
- Check multimedia fuse in the fuse box
→ Replace fuse and re-test
- Check multimedia fuse in the fuse box
- Main cable (Connection/Power)
- Check connection status of H/U ↔ main power (B)
→ If connection is loose or disabled, reconnect and check
- If connection status is normal, contact may be bad, So shake the cable and check
- → If defect is dependent on shaking cable, check cable and connector
H/U Input power (Approx. 14.4V)
(Yellow: B+, Red: ACC)
- → If no power, check cable connection
- → If power is good, replace H/U
- → If defect is dependent on shaking cable, check cable and connector
- Check connection status of H/U ↔ main power (B)
(3) TSB application - Check related TSB, apply latest H/W and S/W
(4) Check H/U defect - Replace H/U
- Duplicate issue during IGN ON (BATT, ACC Power on) is it intermittent?
- Power does not turn off
Inspection Description (1) Duplicate issue - Duplicate issue during IGN ON (BATT, ACC Power on), is it intermittent?
→ If unable to duplicate, proceed with test driving
(2) External/Environmental issue - Vehicle modification
- Cable connection
- Vehicle modification
- Custom Navigation installed/black box power on/Reception related modification
- Main cable connection (Connection/Power)
H/U Power (Approx. 14.4V)
(Yellow: B+, Red: ACC)
- →If no power, check cable connection
- →If power is good, replace H/U
(3) TSB - Check related TSB, apply latest H/W and S/W
(4) Check H/U defect - Replace H/U
- Duplicate issue during IGN ON (BATT, ACC Power on), is it intermittent?
- Power on/off by itself
Inspection Description (1) Duplicate issue - At Gear P, power on and see if problem duplicates
- Duplicate issue using steering wheel
→ If unable to duplicate, proceed with test driving
(2) External/Environmental issue - Vehicle modification
- Cable connection
- Related parts
- Vehicle modification
- Custom Navigation installed/black box power on/Reception related modification
- Main cable (Connection/Power)
- Check connection status of H/U ↔ main power (B)
→ If connection is loose or disabled, reconnect and check
- If connection status is normal, contact may be bad, So shake the cable and check
→ If defect is dependent on shaking cable, check cable and connector
- Check connection status of H/U ↔ main power (B)
- Check related parts. (Handle remote controller, clock spring.)
- Rotate handle while the vehicle is not moving, and check defect
- → If defect is dependent on handle rotation, Check related parts.
(Handle remote controller, clock spring.)
- → If they have no problem, replace H/U
(Foreign matter or internal defect is suspected)
- Defective clock spring and damaged cable has caused defect.
* Clock spring: Electrical device to control handle remote controller switch and supply power to horn and air bag controller.
- → If defect is dependent on handle rotation, Check related parts.
- Rotate handle while the vehicle is not moving, and check defect
(3) TSB - Check related TSB, apply latest H/W and S/W
(4) Check H/U Defect - Replace H/U
- Vehicle battery problem
Inspection Description (1) Duplicate issue - After IGN off, measure voltage
- Normal spec: Refer to each vehicle spec
(2) External/Environmental issue - Vehicle modification
- Black box battery
- MM CAN communication
- Vehicle modification
- Custom Navigation installed/black box power on/Reception related modification
- Black box battery connection
- Check MM CAN status using CAN TOOL. (Refer to #10 CAN)
(3) TSB - Check related TSB, apply latest H/W and S/W
(4) Check H/U Defect - Replace H/U
- After IGN off, measure voltage
- H/U Reset/Error message
Inspection Description (1) Duplicate issue - IGN ON, duplicate issue
(2) External/Environmental issue - Vehicle modification
- Vehicle modification
- Custom Navigation installed/black box power on/Reception related modification
(3) TSB - Check related TSB, apply latest H/W and S/W
(4) Check H/U Defect - Replace H/U
- No display
Inspection Description (1) Duplicate issue - Duplicate issue after IGN ON
(2) External/Environmental issue - Vehicle modification
- Vehicle modification
- Custom Navigation installed/black box power on/Reception related modification
(3) TSB - Check related TSB, apply latest H/W and S/W
(4) Check H/U Defect - Replace H/U
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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