Kia Niro: Intake And Exhaust System / Exhaust Heat Recovery System(EHRS) Troubleshooting

Kia Niro 2017 (DE HEV) Service Manual / Engine Mechanical System / Intake And Exhaust System / Exhaust Heat Recovery System(EHRS) Troubleshooting

Troubleshooting

Symptom		Inspection		Remedy
Overheating	• Engine overheating • Temperature gauge rising to HI	• Inspect GDS/KDS scanner.	① Check DTC code. ② By using KDS/GDS, check for current flowing in wiring connecting to WTS.	Additionally inspect wiring and connector.
		• Inspect coolant leakage.	Inspect leakage from EHRS and coolant tube (including WTS assembly). (Visually check for signs of efflorescence after evaporation of coolant.)	For unit failure, replace EHRS and coolant tube.
		• Inspect operation of EHRS valve (vehicle inspection).	Drive until the engine coolant is sufficiently warmed up, and then inspect operation of wax actuator.[Visually check the lifting amount of wax actuator: Over 8 mm (0.315 in.) at 80°C (176°F), or over 9 mm (0.354 in.) at 90°C. (194°F)]	For unit failure, replace EHRS.
		• Inspect operation of EHRS valve (unit inspection).	① Remove the wax actuator. ② Rotate the valve lever to check for smooth operation.	For unit failure, replace EHRS.

Symptom		Inspection		Remedy
Overheating	• Engine overheating • Temperature gauge rising to HI	• Inspect operation of wax actuator.	① Remove the wax actuator. ② Immerse wax actuator in water and gradually heat the water. ③ Inspect the opening temperature and forward stroke of the valve. [Opening temperature: 71 ± 2°C (159.8 ± 35.6°F), Forward stroke : at 80°C (176°F) 8.85 ± 0.65 mm (0.348 ± 0.026 in.]	For unit failure, replace EHRS.
		• Inspect WTS.	① Remove the WTS. [Disconnect connector (a). → Remove clip (b).] ② Immerse temperature detector of WTS in water and gradually heat the water. ③ Check the resistance according to temperature. [20°C (68°F) : 2.45 ± 0.14 kΩ, 110°C (230°F) : 0.1471 ± 0.002 kΩ]	For unit failure, replace WTS.

Exhaust Heat Recovery System(EHRS) Description and operation

Description and Operation During cold start or in winter, the fuel efficiency can be improved by heating up the coolant with the exhaust gas heat discharged after combusting the engine. ...

Exhaust Heat Recovery System(EHRS) Repair procedures

Removal and Installation 1. Remove the engine room under cover. (Refer to Engine and Transaxle Assembly - "Engine Room Under Cover") 2. ...

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