Hyundai Santa Fe: Auto Lighting Control System / Auto Light Sensor. Repair procedures

Check if the auto light control operates like a timing chart shown below. Tail lamp output and head lamp (Low) output is controlled based on the auto light sensor's input (illumination intensity) when the Auto Light Switch in Multi-Function Switch is turned ON, and the vehicle is in IGN1 or IGN2 ON Mode. If IGN1 = ON, BCM detects this voltage, and if the voltage exceeds rated voltage, then auto light failure occurs. (below 4V or above 6V)

In the state of IGN1 ON, when multi function switch module detects auto light switch on, tail lamp relay output and head lamp low relay output are controlled according to auto light sensor's input.The auto light control doesn't work if the pin sunlight supply (5V regulated power from Ignition 1 power to sunlight sensor) is in short circuit with the ground.If IGN1 ON, The BCM monitors the range of this supply and raises up a failure as soon as the supply’s voltage is out of range. Then this failure occurs and as long as this is present, the head lamp must be turned on without taking care about the sunlight level provided by the sensor.This is designed to prevent any head lamp cut off when the failure occurs during the night.

Schematic diagrams

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Auto Head Lamp Leveling Device

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Other information:

Hyundai Santa Fe (TM) 2019-2024 Service Manual: Troubleshooting

Trouble Symptom Charts Trouble Symptom 1 Trouble Symptom 2 Trouble symptom Probable cause Remedy The set vehicle speed varies greatly upward or downward "Surging" (repeated alternating acceleration and deceleration) occurs after setting Malfunction of the vehicle speed sensor circuit Repair the vehicle speed sensor system, or replace the part Malfunction of ECM Check input and output signals at ECM Trouble Symptom 3 Trouble symptom Probable cause Remedy The CC system is not canceled when the brake pedal is depressed Damaged or disconnected wiring of the brake pedal switch Repair the harness or replace the brake pedal switch Malfunction of the ECM signals Check input and output signals at ECM Trouble Symptom 4 Trouble symptom Probable cause Remedy The CC system is not canceled when the shift lever is moved to the "N" position (It is canceled, however, when the brake pedal is depressed) Damaged or disconnected wiring of inhibitor switch input circuit Repair the harness or repair or replace the inhibitor switch Improper adjustment of inhibitor switch Malfunction of the ECM signals Check input and output signals at ECM Trouble Symptom 5 Trouble symptom Probable cause Remedy Cannot decelerate (coast) by using the "SET/–" switch Temporary damaged or disconnected wiring of "SET/–" switch input circuit Repair the harness or replace the "SET/–" switch Malfunction of the ECM signals Check input and output signals at ECM Trouble Symptom 6 Trouble symptom Probable cause Remedy Cannot accelerate or resume speed by using the "RES/+" switch Damaged or disconnected wiring, or short circuit, or "RES/+" switch input circuit Repair the harness or replace the "RES/+" switch Malfunction of the ECM signals Check input and output signals at ECM Trouble Symptom 7 Trouble symptom Probable cause Remedy CC system can be set while driving at a vehicle speed of less than 40km/h (25mph), or there is no automatic cancellation at that speed Malfunction of the vehicle-speed sensor circuit Repair the vehicle speed sensor system, or replace the part Malfunction of the ECM signals Check input and output signals at ECM Trouble Symptom 8 Trouble symptom Probable cause Remedy The cruise main switch indicator lamp does not illuminate (But CC system is normal) Damaged or disconnected bulb of cruise main switch indicator lamp Repair the harness or replace the part...

Hyundai Santa Fe (TM) 2019-2024 Service Manual: Rear Transverse Trim. Components and components location

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