Hyundai Sonata LF: Cruise Control System / Cruise Control Switch Schematic Diagrams

Troubleshooting

Trouble Symptom Charts Trouble Symptom 1 Trouble Symptom 2 Trouble symptomProbable causeRemedyThe set vehicle speed varies greatly upward or downward"Surging" (repeated alternating acceleration and deceleration) occurs after settingMalfunction of the vehicle speed sensor circuitRepair the vehicle speed sensor system, or replace the partMalfunction of ECMCheck input and output signals at ECM Trouble Symptom 3 Trouble symptomProbable causeRemedyThe CC system is not canceled when the brake pedal is depressedDamaged or disconnected wiring of the brake pedal switchRepair the harness or replace the brake pedal switchMalfunction of the ECM signalsCheck input and output signals at ECM Trouble Symptom 4 Trouble symptomProbable causeRemedyThe 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 circuitRepair the harness or repair or replace the inhibitor switchImproper adjustment of inhibitor switchMalfunction of the ECM signalsCheck input and output signals at ECM Trouble Symptom 5 Trouble symptomProbable causeRemedyCannot decelerate (coast) by using the "SET/–" switchTemporary damaged or disconnected wiring of "SET/–" switch input circuitRepair the harness or replace the "SET/–" switchMalfunction of the ECM signalsCheck input and output signals at ECM Trouble Symptom 6 Trouble symptomProbable causeRemedyCannot accelerate or resume speed by using the "RES/+" switchDamaged or disconnected wiring, or short circuit, or "RES/+" switch input circuitRepair the harness or replace the "RES/+" switchMalfunction of the ECM signalsCheck input and output signals at ECM Trouble Symptom 7 Trouble symptomProbable causeRemedyCC system can be set while driving at a vehicle speed of less than 40km/h (25mph), or there is no automatic cancellation at that speedMalfunction of the vehicle-speed sensor circuitRepair the vehicle speed sensor system, or replace the partMalfunction of the ECM signalsCheck input and output signals at ECM Trouble Symptom 8 Trouble symptomProbable causeRemedyThe cruise main switch indicator lamp does not illuminate (But CC system is normal)Damaged or disconnected bulb of cruise main switch indicator lampRepair the harness or replace the part...

Cruise Control Switch Repair procedures

Inspection [Measuring Resistance] 1. Disconnect the cruise control switch connector from the control switch. 2. Measure resistance between terminals on the control switch when each function switch is ON (switch is depressed)...

Other information:

Hyundai Sonata LF 2014-2019 Service Manual: Electric Parking Brake (EPB) Repair procedures

EPB Release 1. Turn ignition switch OFF and disconnect the negative (-) battery cable. 2. Connect the GDS to the data link connector located underneath the dash panel. 3. Select and operate according to the instructions on the GDS screen. (1) Select vehicle name...

Hyundai Sonata LF 2014-2019 Service Manual: A/C Pressure Transducer Description and Operation

Description The A/C Pressure Transducer (APT) converts the pressure value of high pressure line into voltage value after measuring it. By converted voltage value, engine ECU controls the cooling fan by operating it high speed or low speed. Engine ECU stops the operation of the compressor when the temperature of refrigerant line is very high or very low irregularly to optimize air conditioning system...