Heater System Hyundai Elantra I

DESCRIPTION

The heater system consists of a blower, air inlet assembly, heater unit, heater control panel and heater valve. On Excel and Precis models, a lever type or rotary knob (vacuum type) control panel is used. Scoupe and Sonata use vacuum type controls.

Excel & Precis

The fresh air inlet door is used to select outside (fresh) air or inside (recirculated) air. Setting recirculation/fresh control lever to FRESH position allows outside air to enter. Setting recirculation/fresh control lever to RECIRC position recirculates inside air. The air blend door is always open and admits recirculated air regardless of position of fresh air inlet door.

The heater unit houses, heater core, temperature door and vent/defroster door. (Scheme 1) Heater core's coolant flow is controlled by a heater valve, which is located on the left side of blower motor assembly.

Scheme 1

Airflow control lever controls the flow of air to selected vents by mechanically opening mode doors. Air can be directed to the floor, dashboard or defrost outlets. Airflow lever can be set to FACE, BI-LEVEL, FLOOR, FLOOR/DEFROST or DEFROST.

Setting the lever to FACE position directs air to dashboard vents. Selecting the BI-LEVEL position allows cooler airflow to dashboard vents and warmer air to floor outlets. Selecting the FLOOR position directs airflow to floor outlets. Selecting the FLOOR/DEFROST position allows airflow to floor and defroster outlets. Selecting the DEFROST position directs airflow to defrost outlets.

Move fresh/recirculation control lever to RECIRC position. The vent/fresh mode door closes off the outside vent to heater blower motor housing. Move the fresh/recirculation control lever to FRESH position. The vent/fresh mode door opens to let outside air into heater blower housing to be vented through outlets selected by mode lever.

The temperature control lever mechanically controls flow of engine coolant entering heater core, thus regulating air temperature entering passenger compartment.

Elantra, Scoupe & Sonata

The airflow control knob controls airflow to selected vents by directing source vacuum to vacuum motors. (Scheme 2)or (Scheme 3). Airflow can be directed to floor, dashboard or defrost outlets. The airflow knob can be set to FACE, BI-LEVEL, FLOOR, FLOOR/DEFROST or DEFROST. Setting the lever to FACE position directs airflow to dashboard vents.

Selecting the BI-LEVEL position allows cooler airflow to dashboard vents and warmer air to floor outlets. Selecting the FLOOR position directs airflow to floor outlets. Selecting the FLOOR/DEFROST position allows airflow to floor and defroster outlets. Selecting the DEFROST position directs airflow to defrost outlets.

Scheme 2

Scheme 3

When the air intake button is depress vacuum is applied to fresh/recirculation air vacuum motor, opening the mode door allowing outside airflow into passenger compartment through selected vents.

The control panel has 3 function knobs, fan speed knob, airflow control knob, temperature control knob. Selecting combinations of these knob positions allows adjustment of both air temperature and airflow control to compartment outlets. The air control knob directs source vacuum to vacuum motors which operate appropriate mode door.

FAN SPEED CONTROL KNOB

The fan speed control knob operates fan speed in one of 4 fan speeds, fresh or recirculated air is then blown through selected vents into passenger compartment.

HEATER ASSEMBLY

Heater unit houses, heater core, vent/defrost mode door, temperature blend mode door and fresh/recirculation mode door. Coolant flows continually through the heater core. The amount of heat is controlled by blending air across the heater core with fresh/ recirculation air being vented to selected outlets.

TEMPERATURE CONTROL KNOB

Temperature control knob mechanically adjusts the blend door opening, controlling airflow volume across the heater core. Airflow from the heater core is blended with fresh or recirculated air and vented into passenger compartment through selected outlets. (Scheme 4)

ABNORMAL SOUND FROM HEATER BLOWER MOTOR

Foreign material in heater blower. Damaged blower or blower motor or loose mounting bolts.

MODE CONTROL LEVER

Place mode control lever in DEFROST position. Ensure air flows from defroster ducts. Place mode lever in HEAT position, air should flow from heater outlets. With mode control lever in VENT or BI-LEVEL position, ensure air flows from floor and panel outlets.

TEMPERATURE CONTROL LEVER

Place temperature control lever in COLD position. Position heater valve shaft in fully closed position. Ensure valve opens fully with temperature control lever in HOT position.

NO VENTILATION

Fresh/recirculation mode control cable broken or incorrectly adjusted. Loose duct connection in heater assembly.

Excel & Precis (Lever System)

Heater control cable retaining clip broken or missing. Incorrect cable adjustment at heater valve. Broken heater valve cable. Engine coolant level low. Stuck or clogged heater control valve.

Elantra, Scoupe & Sonata (Vacuum System)

Heater control cable retaining clip broken or missing. Incorrect heater cable adjustment at blend mode door or control panel.

In FLOOR Position, All Air Comes Through Defrost Or Floor

Vents

Blue and or red vacuum hose pinched or disconnected. Black vacuum source hose pinched or disconnected. Vacuum source pinched or disconnected at manifold or vacuum bottle. Defective vacuum motor. (Scheme 4), (Scheme 5) and (Scheme 6).

Scheme 4

Scheme 5

Scheme 6

In DEFROST/FLOOR Position, All Air Comes Through Defrosters

Blue vacuum hose pinched or disconnected at vacuum motor. Black vacuum source hose pinched or disconnected. Vacuum source pinched or disconnected at manifold or vacuum bottle. Defective vacuum motor.

In PANEL VENT Position, All Air Comes Out Of Defrosters

Yellow vacuum hose pinched or disconnected at vacuum motor. Black vacuum source hose pinched or disconnected. Vacuum source pinched or disconnected at manifold or vacuum bottle. Defective vacuum motor.

In PANEL/FLOOR Position, All Air Comes Out Of Defroster or

Panel

Yellow vacuum hose pinched or disconnected at vacuum motor. Blue hose pinched or disconnected at vacuum motor. Black vacuum source hose pinched or disconnected. Vacuum source pinched or disconnected at manifold or vacuum bottle. Defective vacuum motor.

In DEFROST Position, No Vacuum To Recirculation Vacuum Motor

In RECIRC Position, All Air Comes Out Fresh

White vacuum hose disconnected at recirculation vacuum motor. Black vacuum source hose pinched or disconnected. Vacuum source pinched or disconnected at manifold or vacuum bottle. Defective vacuum motor.

BLOWER MOTOR

1. Blower motor is located in blower motor housing, behind right lower crash pad. Disconnect blower motor electrical connector. Remove retaining screws. Remove blower motor from case.
2. Holding blower motor securely, check for abnormal noise, bent fan shaft and cracked or damaged blower fan. If blower motor shaft or fan are damaged, replace defective part as needed.
3. Carefully connect jumper leads from battery negative and positive posts directly to blower motor terminals. Ensure motor operates smoothly. Reverse jumper leads, ensure motor operates smoothly in the reverse direction. If blower motor is inoperative or makes abnormal noise, replace blower motor.

BLOWER MOTOR RESISTOR

1. The blower motor resistor is mounted in the blower motor housing, behind right side lower crash pad. Disconnect blower resistor electrical connector. Unscrew retaining screws and remove resistor from housing.
2. Using an ohmmeter, check resistance between terminals No. 1 and No. 2 (thermal fuse). If continuity does not exist, replace resistor. Check resistance between resistor terminals. See BLOWER RESISTOR RESISTANCE table. (Scheme 7)

BLOWER RESISTOR RESISTANCE

Scheme 7

Elantra, Excel, Precis & Scoupe

1. Blower motor relay is located on relay board below instrument cluster to left of steering column. With ignition and blower motor switches in ON positions, check for voltage at terminals No. 1 and 4 of relay. Terminal numbers are molded into plastic housing. If battery voltage exists, go to step 3).
2. If battery voltage does not exist, check fusible links and all fuses. If fuses are okay, repair open circuit between fuse block and fusible links or fuse block and relay board.
3. Using an ohmmeter, check for continuity between terminals No. 1 and 3. If continuity does not exist, replace relay. If continuity exists, apply battery voltage to terminal No. 1 and ground terminal No. 3. Using an ohmmeter, check for continuity between terminals No. 2 and 4. If continuity does not exist, replace relay.

Sonata

1. Blower motor relay is located on relay board in engine compartment next to left strut tower. Terminal numbers are molded into plastic housing. With ignition and blower motor in the ON positions, check for voltage at terminals "L" and S1 of relay.
2. If battery voltage does not exist, check fusible links and all fuses. If fuses are okay, repair open circuit between fuse block and fusible links or fuse block and relay board.
3. Using an ohmmeter, check for continuity between terminals "L" and "B". If continuity does not exist, replace relay. If continuity exists, apply battery voltage to terminal "L", and ground terminal "B". Using an ohmmeter, check for continuity between terminals S1 and S2. If continuity does not exist, replace relay.

Removal & Installation (Excel & Precis)

Disconnect negative battery cable. Remove control panel retaining screws, and pull out control panel. Remove cable retaining clip from heater box. Remove cable at mode door arm. Remove cable retaining clip at control panel. Disconnect airflow control cable from control panel. To install, reverse removal procedure. Inspect cable and mode cam to ensure good working condition.

Removal & Installation

Disconnect battery ground cable and wiring at blower motor. Remove retaining screws. Pull out blower motor. Remove retaining clip holding fan to motor and remove fan. To install, reverse removal procedure.

Pull out ashtray and remove bolt. Remove lower center fascia panel. Remove heater control panel retaining screws and heater control panel. Disconnect electrical connections and cable clips. Remove cables from control panel. On rotary knob models, disconnect vacuum connector. To install, reverse removal procedure.

Removal

1. Disconnect negative battery cable. Set temperature control lever to HOT position and drain coolant. Remove heater hoses. Remove center console assembly, ECU and mounting bracket.
2. Remove center fascia panel. Remove glove box assembly and main lower crash pad assembly. Remove heater control assembly. Remove left lower crash pad and center support bracket assembly. Remove evaporator unit (if equipped).
3. Loosen rear heating duct mounting screw. Push on rear of heating joint duct and pull duct out. Remove blower heater duct. Loosen heater mounting bolts. Remove heater unit. (Scheme 1), (Scheme 2) or (Scheme 3).

Installation

Check link mechanism for operation. Check heater core for clogging or coolant leakage. Check heater valve for operation and clogging. To install, reverse removal procedure.

1. Remove steering wheel and steering column upper and lower shroud. Remove cassette player and radio. Remove lower center fascia assembly. Remove driver's side lower crash pad. Remove hood release handle mounting screws.
2. Remove left side lower instrument panel. Remove right side main lower crash pad. Remove glove box. Disconnect the speedometer cable and electrical connectors from instrument cluster and remove the cluster assembly. Remove heater control assembly. Remove right and left front speaker grills. Remove main instrument panel. To install, reverse removal procedure.

Disconnect battery ground cable. Remove control panel retaining screws and pull out control panel. Remove cable retaining clip from heater box. Remove cable at mode door arm. Remove cable retaining clip at control panel. Disconnect mode control cable from control panel. To install, reverse removal procedure. Inspect cable and mode cam to ensure good working condition.

Disconnect battery ground cable. Remove heater control panel. Remove fresh/recirculation cable from heater control panel. Remove cable retaining clip from fresh/recirculation air mode door. Remove fresh/recirculation air cable. To install, reverse removal procedure. Inspect cable, fresh/recirculation mode pin and fresh/recirculation control arm.

Disconnect battery ground cable. Remove control panel retaining screws. Remove cable from heater control panel. Remove heater control panel. Remove temperature control cover plate at heater housing. Remove temperature control cable retaining clip from heater box. Remove temperature control cable from at mode door arm. To install, reverse removal procedure. Inspect cable, temperature control arm pin and temperature control arm.

Remove front seat. Remove supplement and main console (if equipped). Remove rear heating joint duct and rear heating duct. (Scheme 8) To install, reverse removal procedure.

Scheme 8

Remove instrument panel. See INSTRUMENT PANEL under REMOVAL AND INSTALLATION. Remove side defroster hose. Disconnect vent hose. Remove side register louver. Remove side defroster nozzle and side register louver nozzle. Remove instrument panel upper cover. Remove defroster nozzle. Remove heater connection. Remove center register louver duct. (Scheme 8) To install, reverse removal procedure.

Heater Wiring Diagram (Excel & Precis). Scheme 9

Heater Wiring Diagram (Scoupe). Scheme 10

Heater Wiring Diagram (Sonata). Scheme 11

Heater Wiring Diagram (Elantra). Scheme 12

Heater Wiring Diagram (Excel & Precis). Scheme 13

Heater Wiring Diagram (Scoupe). Scheme 14

Heater Wiring Diagram (Sonata). Scheme 15

See also:
• INSTRUMENT PANEL