A/c-Heater System - Manual Hyundai Elantra I

A/C SYSTEM SPECIFICATIONS

A/C SYSTEM SPECIFICATIONS

DESCRIPTION

Integrated heating/air conditioning system, a blend-air type system, consists of compressor, cooling fan, condenser, receiver-drier, pressure switch, blower motor, evaporator, heater core and a fixed orifice tube. (Scheme 1)

Warm and cool air are mixed in relation to temperature setting on control panel. Outlet location of cooled/warmed air is determined by settings of registers and control panel switches.

Scheme 1

OPERATION

When air conditioning is turned on, clutch plate is engaged and compressor becomes operational. The compressor draws low pressure refrigerant vapor from evaporator and compresses it into high pressure, high temperature vapor.

The vapor is then pumped to the condenser. Outside air passing through condenser absorbs heat from high temperature vapor. As the vapor cools, it turns into high pressure liquid, which then flows to the fixed orifice tube.

The restriction in the fixed orifice tube converts high pressure liquid into low pressure liquid. The low pressure liquid then enters the evaporator. The liquid refrigerant is colder than vehicle interior air so air passing through evaporator coils transfers its heat to the refrigerant. As the refrigerant warms, it boils into gas and is drawn into the compressor to repeat cycle.

COMPRESSOR DOES NOT RUN/RUNS POORLY

1. Check A/C fuse and relay. Replace components if defective. Check wiring for short if A/C fuse blows again. Check compressor clutch field coil continuity. Replace clutch if continuity is not present.
2. Check A/C switch operation. Replace switch if necessary. Check pressure switch. Replace switch if necessary. Check battery voltage. Charge or replace battery if necessary. Check A/C system charge. If charge is low, recharge system and check for leaks.
3. Check for slipping compressor drive belt. If belt is loose, tighten it and recheck system operation. Inspect system for restrictions at fixed orifice tube, receiver-drier, evaporator, condenser and refrigerant lines.

COOL AIR DISCHARGE ONLY AT HIGH SPEEDS

Check for slipping compressor drive belt. Tighten belt if necessary. Check for slipping magnetic clutch. Clean or replace clutch if necessary. Check for correct clearance between clutch drive plate and pulley. Check for restricted condenser. Replace condenser if necessary. Check for refrigerant overcharge.

INTERMITTENT COOL AIR DISCHARGE

Check for excessive moisture in system. Evacuate and recharge system if necessary. Check for compressor clutch slip. Check A/C system for ice-up indicating a restriction. Check A/C system wiring, and repair wiring as necessary.

INSUFFICIENT COOLED AIR VELOCITY

Check for clogged evaporator. Check for air leaking from cooling unit or air duct. Check for blocked air inlet. Check for faulty blower motor.

INSUFFICIENT COOLING

Check for slipping compressor drive belt. Check for faulty compressor clutch, compressor or control switch. Check for refrigerant overcharge, excessive oil in system or clogged receiver-drier.

NO BLOWER OPERATION

Check fuse and relay. Replace components if defective. Check control switch and circuit. Repair or replace components if necessary. Check blower motor operation. Replace motor if necessary.

NO COOLING OR WARM AIR

Check compressor clutch for correct engagement. Check for slipping compressor drive belt. Check A/C fuse and relay. Replace components if defective. Check wiring for short if A/C fuse blows again.Check A/C switch operation.

COMPRESSOR

1. Compressor malfunction will appear as noise, seizure, leakage or low discharge pressure. Resonant compressor noises are acceptable. Irregular noise or rattles may indicate broken parts or excessive clearances due to wear.
2. To check for seizure, remove drive belt. Energize magnetic clutch, and rotate drive plate by hand. If rotation is impossible, compressor is seized.
3. Low discharge pressure may be due to a restriction, faulty compressor internal seal or an insufficient refrigerant charge. If compressor is inoperative but not seized, check for power to magnetic clutch coil terminals.

CONDENSER

1. Condenser may leak or be restricted. Restriction will result in excessive compressor discharge pressure. If partial restriction exists, ice will form immediately downstream of restricted area.
2. If airflow through condenser or radiator is blocked, high discharge pressures will result. During normal condenser operation, outlet pipe will be slightly cooler than inlet pipe.

EVAPORATOR

When evaporator malfunctions, trouble will show up as inadequate supply of cool air. Problem is likely a partially plugged core due to dirt or a blower malfunction.

FIXED ORIFICE TUBE

Located in condenser-to-evaporator refrigerant line, fixed orifice tube converts high pressure liquid refrigerant to low pressure. Fixed orifice tube failures are usually indicated by low suction and discharge pressures. Failure is generally due to restricted internal line.

RECEIVER-DRIER

Replace receiver-drier if it becomes plugged or contaminated, leaks or is left opened for more than 24 hours. An excessively cold receiver-drier outlet indicates a restriction.

REFRIGERANT LINE RESTRICTIONS

A restricted suction line will cause low suction pressure at compressor, low discharge pressure and little or no cooling. A restriction in discharge line generally will cause discharge line to leak. A liquid line restriction will be evident by low discharge and suction pressure and insufficient cooling.

A/C RELAY

Locate A/C relay. (Scheme 2), (Scheme 5), (Scheme 6), (Scheme 7), (Scheme 9) and (Scheme 10). Remove relay. Continuity should not exist between terminals No. 2 and 4. Apply battery voltage to terminal No. 1, and ground terminal No. 3. Continuity should now exist between terminals No. 2 and 4. If continuity is not as specified, replace relay.

Scheme 2

BLOWER MOTOR RESISTOR

Blower motor resistor is mounted in blower motor housing, behind right lower crash pad. (Scheme 3) Disconnect blower resistor electrical connector. Unscrew retaining screws and remove resistor from housing. Check resistance between terminals No. 1 and 2 (thermal fuse) using an ohmmeter. If continuity does not exist, replace resistor. If continuity exists, check resistance between terminals and ground using values shown in the BLOWER RESISTOR RESISTANCE table. (Scheme 3)

BLOWER RESISTOR RESISTANCE

Scheme 3

Except Sonata

Check condenser fan for restriction and damage. If fan is okay, disconnect wiring harness connector. Using an ohmmeter, check for continuity between connector terminals. Continuity should be present. If continuity is not present, replace condenser fan motor.

Sonata

Disconnect wiring harness connector. Using an ohmmeter, check for continuity between terminals "B" and "LW" and between terminals "B" and "LR". (Scheme 4) Continuity should exist. If continuity is not as specified, replace condenser fan motor.

Scheme 4

Except Scoupe

1. Locate condenser fan relay in relay box in engine compartment. (Scheme 5), (Scheme 6), (Scheme 7), (Scheme 8) or (Scheme 10). Unplug relay, and check for continuity between terminals No. 1 and 4. (Scheme 5)through (Scheme 10). If continuity exists, replace relay.
2. If continuity is not present, apply battery voltage to terminals No. 1 and 3. Continuity should be present between terminals No. 2 and 4. If continuity is not present, replace relay.

Scoupe

Locate condenser fan relay in relay box in engine compartment. (Scheme 9) Unplug relay. Apply battery voltage to terminals No. 1 and 2. If continuity does not exist between terminals No. 2 and 3, replace relay.

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

PRESSURE/CYCLING SWITCH

Pressure/cycling switch testing is not available from manufacturer. See PRESSURE/CYCLING SWITCH SPECIFICATIONS table.

PRESSURE/CYCLING SWITCH SPECIFICATIONS

REMOVAL & INSTALLATION

Note. For removal and installation procedures not covered in this article, see appropriate HEATER SYSTEMS article.

1. Discharge A/C system using approved refrigerant recovery/recycling equipment. On Excel, Precis and Scoupe, remove distributor. On all models, loosen tension pulley and remove drive belt. Remove electrical connector, and disconnect hoses. Remove compressor from compressor bracket.
2. Remove and measure amount of oil from compressor. If more than 2.5 ounces are removed, replace amount removed with NEW refrigerant oil. Compressor must have at least 2.5 ounces of refrigerant oil. To install, reverse removal procedure. Evacuate, recharge and test system.

1. Discharge A/C system using approved refrigerant recovery/recycling equipment. Using Line Separator (09977-33600), disconnect discharge hose from condenser inlet fitting.
2. On Excel and Precis, remove radiator grille. On all models, remove radiator. Disconnect liquid line pipe from receiver-drier. Remove condenser and 2 mounting insulators. To install, reverse removal procedure. If NEW condenser is installed, add one ounce of refrigerant oil. Evacuate, recharge and test system.

Removal (Elantra & Sonata)

1. Disconnect negative battery cable. Discharge A/C system using approved refrigerant recovery/recycling equipment. Set temperature control lever to HOT position, and drain coolant. Remove heater hoses. Remove center console assembly, Electronic Control Unit (ECU) and mounting bracket.
2. Remove center fascia panel. Remove glove box assembly and main lower crash pad assembly. Remove control panel assembly. Remove left lower crash pad and center support bracket assembly. Remove evaporator assembly.

Installation

Check linkage mechanism for correct operation. If NEW evaporator is installed, add 3 ounces of refrigerant oil. To install, reverse removal procedure.

Removal & Installation (Excel, Precis & Scoupe)

1. Disconnect negative battery cable. Discharge A/C system using approved refrigerant recovery/recycling equipment. Disconnect outlet and inlet pipes from evaporator, and plug openings. Remove grommets from inlet and outlet tubes. Remove console assembly. Remove instrument panel lower covers and glove box.
2. Remove blower assembly. Remove drain hose. Remove mounting bolts and nuts. Carefully lift out assembly. To disassemble evaporator unit, remove clamps holding upper case to lower case. (Scheme 11)
3. Remove evaporator from lower case. To install, reverse removal procedure. If NEW evaporator is installed, add 3 ounces of refrigerant oil. Evacuate, recharge and test system.

Scheme 11

Note. Receiver-drier should be replaced if it has been exposed to atmosphere for more than 24 hours.

1. Discharge A/C system using approved refrigerant recovery/recycling equipment. Disconnect refrigerant lines to both ends of receiver-drier. Plug or close open ends of refrigerant lines and inlet and outlet ports on receiver-drier.
2. Disconnect pressure switch connector. Remove bracket attaching screws and lift out assembly. Remove receiver-drier from bracket. To install, reverse removal procedure. If NEW receiver-drier is used, add one ounce of refrigerant oil. Evacuate, recharge and test system.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

Manual A/C-Heater System Wiring Diagram (Elantra). Scheme 12

Manual A/C-Heater System Wiring Diagram (Excel & Precis). Scheme 13

Manual A/C-Heater System Wiring Diagram (Scoupe). Scheme 14

Manual A/C-Heater System Wiring Diagram (Sonata). Scheme 15

See also:
• BLOWER RESISTOR RESISTANCE