A/c-Heater System - Automatic Buick LeSabre VII

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

Scheme 1

DESCRIPTION

The system automatically maintains selected in-vehicle temperature. All models feature a self-diagnostic function in the microprocessor. If a fault occurs, a trouble code will be set in memory.

A/C-HEATER CONTROL PANEL

Buttons on the A/C-heater control panel select operating modes, in-vehicle temperature, blower motor speed, and outside air temperature display. An auxiliary control panel allows the front seat passenger to adjust temperature independently.

PROGRAMMER

The programmer converts electrical signals from the A/C-heater control panel into vacuum commands for air intake and distribution door actuators, and into speed control signals to the blower motor.

TEMPERATURE SENSORS

In-vehicle and outside (ambient) air temperature sensors provide basic control inputs for the system. The microprocessor uses these sensor inputs to generate command signals for the programmer.

BLOWER CONTROL MODULE

The blower control module receives command signals from the A/C-heater control panel, and amplifies and applies the signals to the blower motor to vary its speed. Command signals are based on blower setting and mode selection at the control panel, selected temperature, and difference between in-vehicle and selected temperature.

A/C COMPRESSOR CONTROL RELAY

The A/C compressor control relay cycles the compressor on or off by energizing the compressor clutch coil. This relay is controlled by the PCM.

PRESSURE CYCLING SWITCH

This switch monitors system low-side pressure, which is a function of evaporator temperature. The PCM monitors the signal from this switch to cycle the compressor on and off.

A/C HIGH PRESSURE CUT-OFF SWITCH

This switch provides compressor protection by opening the compressor clutch circuit if high-side pressure exceeds approximately 430 psi (30 kg/cm 2 ). When pressure falls below 200 psi (14 kg/cm 2 ), the switch closes and again allows compressor operation.

ORIFICE TUBE

The orifice tube meters liquid refrigerant flow into the evaporator. The orifice tube has filter screens on inlet and outlet sides. The tube has no moving parts and is not adjustable. If it is plugged or defective, it must be replaced.

AIR MIX VALVE

1. Remove glove box. Start engine. Set temperature control to 90°F (33°C). Set passenger control panel to full WARM position. If outside temperature is higher than 90°F (33°C), unplug in-vehicle temperature sensor. Allow at least 45 seconds for programmer output cranks to reach full heating position.
2. Gently pull driver air mix valve crank toward programmer until valve contacts stop. Insert threaded portion of link into slot on plastic pin on driver air mix valve crank.
3. Gently pull passenger air mix valve crank toward actuator until valve contacts stop. Insert threaded portion of link into slot on plastic pin on passenger air mix valve crank. (Scheme 2)

Scheme 2

TROUBLE SHOOTING

See TROUBLE SHOOTING in the A/C-HEATER SYSTEM - MANUAL article in the AIR CONDITIONING & HEAT section.

ENTERING SELF-DIAGNOSTICS

Turn ignition on. Connect Tech 1 scan tester to Data Link Connector (DLC). DLC is located under instrument panel, near steering column. Retrieve codes, following manufacturer's instructions. See DIAGNOSTIC TROUBLE CODE (DTC) table. Refer to appropriate test procedure. To test individual components, see TESTING . Clear codes after completing repairs. See CLEARING CODES .

DIAGNOSTIC TROUBLE CODE (DTC)

CLEARING CODES

Manufacturer recommends clearing codes by following instructions included with Tech 1 scan tester.

SYSTEM CHECK

1. Turn ignition on. Retrieve codes. If any codes exist, go to next step. If no codes exist, go to step 4).
2. If only history codes exist, go to next step. If both current and history codes exist, first make necessary repairs to clear current codes and clear history codes. See «DIAGNOSTIC TROUBLE CODE (DTC)»(/buick/lesabre/vii-1992-1999/remont/automatic-hvac-system/#ac-heater-system-automatic). If there are any history-only codes remaining, go to next step.
3. Perform all applicable steps of Air Conditioning Response Chart. (Scheme 3) If the current DTC resets, refer to «DIAGNOSTIC TROUBLE CODE (DTC)»(/buick/lesabre/vii-1992-1999/remont/automatic-hvac-system/#ac-heater-system-automatic). If the current DTC does not reset, inspect all wiring and connectors for intermittent connections. Repair as necessary.
4. Perform all applicable steps of Air Conditioning Response Chart. (Scheme 3) If system does not respond properly, refer to «DIAGNOSTIC TROUBLE CODE (DTC)»(/buick/lesabre/vii-1992-1999/remont/automatic-hvac-system/#ac-heater-system-automatic). If system responds properly, no problem is indicated at this time.

Scheme 3

Sunload Sensor Circuit Test

1. Perform SYSTEM CHECK. Park vehicle in well lighted area. Connect Tech 1 scan tester. Turn ignition on. Monitor suspect sunload sensor. Cover suspect sensor with cardboard. Sunload sensors are located at top of dash. If counts increase from earlier value, go to next step. If counts do not increase, go to step 3).
2. Clear codes. Turn ignition off. Turn ignition on. If DTC 008 resets, go to next step. If DTC 008 does not reset, inspect for loose or intermittent connection.
3. Turn ignition off. Unplug suspect sensor. Turn ignition on. Measure voltage at sensor harness connector terminals. If voltage is not approximately 5 volts, go to next step. If voltage is as specified, replace sunload sensor.
4. If voltage is not greater than 5 volts, go to next step. If voltage is greater than 5 volts, repair short to voltage on Blue/Black wire (DTC 008) or Gray wire (DTC 015).
5. Measure voltage between sensor harness connector terminal "A" (Blue/Black or Gray wire) and DLC terminal No. 4. (Scheme 4) If voltage is about 5 volts, go to next step. If voltage is not as specified, go to step 7).
6. If no other sensor codes exist, repair open circuit in Black/White wire associated with suspect sensor. If all other sensor codes exist, inspect circuit No. 1704 (Black/White wire) for open circuit. If circuit is okay, replace programmer.
7. If DTC 008 exists, backprobe between programmer terminal E15 (Gray wire) and DLC terminal No. 4. If DTC 015 exists, backprobe between programmer terminal F10 (Blue/Black wire) and DLC terminal No. 4. If voltage is approximately 5 volts, repair open Gray or Blue/Black wire. If voltage is not as specified, temporarily install known good programmer, then retest system.

Scheme 4

Outside Temperature Sensor Circuit Test

1. Perform SYSTEM CHECK. Turn ignition off. Unplug connector from outside air temperature sensor, located at lower end of center radiator brace. Measure resistance between sensor terminals. See «OUTSIDE AIR TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS»(/buick/lesabre/vii-1992-1999/remont/automatic-hvac-system/#ac-heater-system-automatic) . If sensor resistance is as specified, go to next step. Replace sensor if resistance is not approximately as specified. OUTSIDE AIR TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS °F (°C) Ohms 14 (-10) 5270-5980 23 (-5) 4030-4520 32 ( 0) 3110-3440 50 (10) 1910-2070 68 (20) 1210-1280 86 (30) 780-820 104 (40) 510-550
2. Turn ignition on. Measure voltage between sensor harness connector terminal "A" (Green/Black wire) and "B" (Black/White wire). If voltage is about 5 volts, go to next step. If voltage is not as specified, go to step 4).
3. Turn ignition off. Reconnect sensor. Turn ignition on. Clear codes. Turn ignition off. Turn ignition on. If DTC 010 resets, inspect wiring and connections. If all are okay, temporarily substitute known good programmer, then retest system.
4. If voltage is not greater than 5 volts, go to next step. If voltage is greater than 5 volts, repair short to voltage on Green/Black wire.
5. Measure voltage between sensor harness connector terminal "A" (Green/Black wire) and ground. If voltage is about 5 volts, go to next step. If voltage is not as specified, go to step 7).
6. If no other sensor codes exist, repair open circuit in Black/White wire associated with suspect sensor. If all other sensor codes exist, inspect circuit No. 1704 (Black/White wire) for open circuit. If circuit is okay, temporarily substitute known good programmer, then retest system.
7. Backprobe between programmer terminal F8 (Green/Black wire) and DLC terminal No. 4. If voltage is approximately 5 volts, repair open Green/Black wire. If voltage is not as specified, temporarily substitute known good programmer, then retest system.

Inside Air Temperature Sensor Circuit Test

1. Perform SYSTEM CHECK. Turn ignition off. Unplug connector from inside air temperature sensor, located under center of dash. Measure resistance between sensor terminals. See «INSIDE AIR TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS»(/buick/lesabre/vii-1992-1999/remont/automatic-hvac-system/#ac-heater-system-automatic) . If sensor resistance is as specified, go to next step. Replace sensor if resistance is not approximately as specified. INSIDE AIR TEMPERATURE SENSOR RESISTANCE SPECIFICATIONS °F (°C) Ohms 14 (-10) 15,420-16,890 23 (-5) 11,760-12,800 32 (0) 9030-9750 50 (10) 5470-5850 68 (20) 3410-3610 86 (30) 2170-2290 104 (40) 1410-1500
2. Turn ignition on. Measure voltage between sensor harness connector terminal "A" (Dark Green wire) and "B" (Black/White wire). If voltage is about 5 volts, go to next step. If voltage is not as specified, go to step 4).
3. Turn ignition off. Reconnect sensor. Turn ignition on. Clear codes. Turn ignition off. Turn ignition on. If DTC 013 resets, inspect wiring and connections. If all are okay, temporarily substitute known good programmer, then retest system.
4. If voltage is not greater than 5 volts, go to next step. If voltage is greater than 5 volts, repair short to voltage on Dark Green wire.
5. Measure voltage between sensor harness connector terminal "A" (Dark Green wire) and Data Link Connector (DLC) terminal No. 4. If voltage is approximately 5 volts, go to next step. If voltage is not as specified, go to step 7).
6. If no other sensor codes exist, repair open circuit in Black/White wire associated with suspect sensor. If all other sensor codes exist, inspect circuit No. 1704 (Black/White wire) for open circuit. If circuit is okay, temporarily substitute known good programmer, then retest system.
7. Backprobe between programmer terminal F7 (Dark Green wire) and DLC terminal No. 4. If voltage is approximately 5 volts, repair open Dark Green wire. If voltage is not as specified, temporarily substitute known good programmer, then retest system.

Passenger Control E & C Data Line Test

1. Perform SYSTEM CHECK. Turn ignition off. Unplug Passenger Climate Control (PCC). Turn ignition on. Measure voltage between harness connector terminals "B" (Tan wire) and "E" (Blue/White wire). If voltage is approximately 5 volts, go to next step. If voltage is not as specified, go to step 6).
2. Turn ignition off. Reconnect passenger climate control. Unplug programmer harness connector. Turn ignition on. Measure voltage between harness connector terminals F14 (Black wire) and E1 (Black/White wire). If voltage is 10-11 volts, go to next step. If voltage is not as specified, go to step 4).
3. Turn ignition off. Unplug passenger climate control harness connector. Measure resistance between passenger climate control connector terminals while setting temperature as specified. See «PASSENGER CLIMATE CONTROL RESISTANCE SPECIFICATIONS»(/buick/lesabre/vii-1992-1999/remont/automatic-hvac-system/#ac-heater-system-automatic) . If resistance is within specification, inspect all wiring for poor or intermittent connections. If resistance is not within specification, replace passenger climate control. PASSENGER CLIMATE CONTROL RESISTANCE SPECIFICATIONS Setting Ohms Full Cold 5200-5500 (Center) 27,500-28,500 Full Hot 10,200-10,700
4. If battery voltage does not exist, go to next step. If battery voltage exists, repair short to voltage on Black wire.
5. Turn ignition off. Unplug harness connector from passenger climate control. Backprobe programmer terminals E1 (Black/White wire) and F14 (Black wire). If voltage is 10-11 volts, repair open circuit No. 1878 (Black wire). If voltage is not as specified, inspect terminals for proper contact. If terminals are okay, temporarily substitute known good programmer, then retest system.
6. If voltage is not greater than 5 volts, go to next step. If voltage is greater than 5 volts, repair short to voltage on circuit No. 831 (Dark Blue/White wire).
7. Measure voltage between PCC terminal "E" and DLC terminal No. 4. If voltage is approximately 5 volts, go to next step. If voltage is not as specified, go to step 9).
8. Backprobe between programmer terminals E12 (Brown wire) and F9 (Tan wire). If battery voltage exists, repair open Tan wire. If battery voltage does not exist, go to step 10).
9. Backprobe between programmer terminals F9 (Tan wire) and F16 (Dark Blue/White wire). If voltage is not approximately 5 volts, go to next step. If voltage is approximately 5 volts, go to step 11).
10. Inspect programmer connector and terminals for proper contact. If all terminals are okay, temporarily substitute known good programmer, then retest system.
11. Measure voltage between PCC harness connector terminals "A" and "E". If battery voltage exists, repair short to ground on circuit No. 831 (Dark Blue/White wire). If battery voltage does not exist, repair open circuit No. 831 (Dark Blue/White wire).

A/C-Heater Control E & C Data Line Test

1. Perform SYSTEM CHECK. Turn ignition off. Unplug harness connector from A/C-heater control. Turn ignition on. Select HVAC DTC on Tech 1 scan tester. Connect jumper wire between harness connector terminals B1 (Light Blue wire) and B2 (Purple wire). If DTC 35 does not change from current to history, go to next step. If DTC 35 changes to history, temporarily substitute known good A/C-heater control, then retest system.
2. Turn ignition off. Unplug harness connector from A/C-heater control. Turn ignition on. Measure voltage between harness connector terminals A8 (Black wire) and B1 (Light Blue wire). If voltage is not approximately 8 volts, go to next step. If voltage is approximately 8 volts, go to step 4).
3. Backprobe programmer connector terminals E1 (Black/White wire) and E16 (Purple wire). If voltage is approximately 8 volts, repair open Purple wire between programmer and A/C-heater control panel. If voltage is not as specified, inspect for proper terminal contact. If connections are okay, temporarily substitute known good programmer, then retest system.
4. Reconnect A/C-heater control. Press OFF button. Backprobe harness connector terminals B1 (Light Blue wire) and B2 (Purple wire). If voltage is approximately 3.5 volts, go to next step. If voltage is not as specified, inspect for proper terminal contact. If terminals are okay, temporarily substitute known good A/C-heater control, then retest system.
5. Backprobe programmer harness connector E1 (Black/White wire) and F12 (Light Blue wire). If voltage is approximately 3.5 volts, inspect connector for proper terminal contact. If terminals are okay, temporarily substitute known good programmer. If voltage is not as specified, repair open circuit No. 1880 (Light Blue wire).

Loss Of Serial Data Test

1. Perform SYSTEM CHECK. Turn ignition on. Connect Tech 1 scan tester. If scan tester can establish communications on circuit No. 800 (Tan wire at DLC), go to next step. If scan tester cannot establish communications, repair as necessary.
2. Attempt to establish communications with AC-heater system. If communication can be established, go to next step. If communications cannot be established, go to step 4).
3. Clear DTC 038. Turn ignition off, then on. If DTC 038 resets, temporarily substitute known good programmer, then retest system. If DTC 038 does not reset, system is okay.
4. Turn ignition off. Unplug programmer connector. Remove terminals E10 (Tan wire) and E11 (Tan wire) from programmer harness connector. Reconnect programmer, leaving Tan wires free. Turn ignition on. Measure voltage at programmer connector cavities for terminals E10 and E11. If voltage is about 5 volts at each cavity, go to next step. If voltage is not as specified, temporarily substitute known good programmer, then retest system.
5. Inspect programmer and harness connector terminals E10 (Tan wire) and E11 (Tan wire) for good contact. Inspect Tan wires for open circuit. Repair as necessary. If all is okay, temporarily install known good programmer, then retest system.

Driver Air Mix Actuator Test

1. Perform SYSTEM CHECK. Turn ignition on. Connect Tech 1 scan tester. Select HVAC. Select DATA PAIR for air mix door No. 1. Set temperature control to full cold position. If scan tester displays commanded door position of 100 percent, go to next step. If scan tester does not display commanded door position of 100 percent, temporarily install known good programmer, then retest system.
2. Set temperature control to full hot position. If scan tester displays commanded door position of 00 percent, go to next step. If scan tester does not display commanded door position of 00 percent, temporarily install known good programmer, then retest system.
3. Compare actual value (ACT) displayed on scan tester with commanded (COM) values. If values agree within 5 percent, go to next step. If values do not agree as specified, temporarily install known good programmer, then retest system.
4. Inspect air mix valve for broken or binding components, or improper adjustment. See AIR MIX VALVE under ADJUSTMENTS. Repair as necessary. If all is okay, temporarily install known good programmer, then retest system.

Passenger Air Mix Actuator Test

1. Perform SYSTEM CHECK. Unplug passenger air mix valve actuator connector, located on programmer. Turn ignition on. Measure voltage between harness connector terminals No. 8 (White wire) and No. 10 (White wire). If voltage is about 5 volts, go to step 3). If voltage is not as specified, go to next step.
2. Inspect passenger air mix valve actuator, associated wiring, and harness connector for loose or poor connections. Repair as necessary. If all is okay, temporarily install known good programmer, then retest system.
3. Measure voltage between harness connector terminals No. 8 (White wire) and No. 10 (White wire). If voltage is about 4 volts, go to step 5). If voltage is not as specified, go to next step.
4. Inspect wiring and connectors between passenger air mix valve actuator and programmer for loose or poor connections. Repair as necessary. If all is okay, temporarily install known good programmer, then retest system.
5. Inspect passenger air mix valve for broken or binding components, or improper adjustment. See «AIR MIX VALVE»(/buick/lesabre/vii-1992-1999/remont/automatic-hvac-system/#ac-heater-system-automatic__air-mix-valve) under ADJUSTMENTS. Repair as necessary. If all is okay, temporarily install known good air mix valve actuator, then retest system.

Loss Of Memory Test

1. Perform SYSTEM CHECK. If battery was not recently disconnected or discharged, go to next step. If battery was recently disconnected or discharged, clear code, then retest system.
2. Clear DTC 052. If DTC 052 resets, go to next step. If DTC does not reset, system is okay.
3. Inspect I/P fuse. If fuse is okay, go to next step. If fuse is blown, inspect for short to ground on circuit No. 40 (Orange wire). Repair as necessary.
4. Turn ignition off. Unplug programmer. Measure voltage between harness connector terminals E1 (Black/White wire) and E13 (Orange wire). If battery voltage exists, inspect programmer and harness connector for improper terminal contact. If all is okay, temporarily install known good programmer, then retest system. If battery voltage does not exist, repair open Black/White or Orange wire.

TESTING

A/C COMPRESSOR CLUTCH CONTROL

See the A/C COMPRESSOR CLUTCH CONTROLS article in the AIR CONDITIONING & HEAT section.

BLOWER MOTOR CIRCUIT TEST

1. Unplug connectors from blower control module, located on lower front side of blower housing, near accumulator. Turn ignition on. Press AUTO button. Press blower HI button. 2) Measure voltage between 2-pin connector terminal "B" (Red wire) and ground. If battery voltage exists, go to next step. If battery voltage does not exist, inspect Red wire for open or short to ground.
2. Measure voltage between 4-pin connector terminal "B" (Gray/Black wire) and ground. (Scheme 5) If meter indicates approximately 8 volts, go to next step. If voltage is not as specified, inspect Gray/Black wire for open or short to ground. If wire is okay, temporarily substitute known good programmer. Retest system.
3. Measure resistance between 4-pin connector terminal "C" (Black wire) and ground. If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair Black wire to ground.
4. Connect fused jumper wire between 2-pin connector terminal "B" (Red wire) and 4-pin connector terminal "A" (Purple wire). If blower motor runs at high speed, go to next step. If blower motor does not run at high speed, inspect Purple and Black wires to blower motor. If wiring is okay, replace blower motor.
5. Turn ignition off. Connect wiring to blower control module and programmer. Turn ignition on. Press AUTO button. Backprobe programmer connector terminal E9 (Gray/Black wire). Press HI button. Voltage should be 6-8 volts. Press LO button. Voltage should be 2-4 volts. If voltages are not as specified, temporarily substitute known good programmer. Retest system. If voltages are as specified, replace blower control module.

Scheme 5

ELECTRIC COOLING FAN

See appropriate C-12 chart in the ENGINE COOLING FANS article in the ENGINE COOLING section.

VACUUM CONTROLS TEST

1. Connect Tech 1 scan tester to DLC connector, located beneath instrument panel. Turn ignition on. Select DATA LIST. Observe solenoids No. 1, 2, 3, and 4. Press HEAT button on A/C-heater control panel. If solenoid No. 3 is on and solenoids No. 1, 2, and 4 are off, go to next step. If solenoids are not as specified, go to step 3).
2. Press AUTO button. Press and hold COOL button until set temperature is 60°F (18°C). If solenoid No. 3 is off and solenoids No. 1, 2, and 4 are on, go to step 4). If solenoids are not as specified, temporarily substitute known good programmer. Retest system.
3. Select TESTS. Command solenoid No. 3 to turn on. If solenoid No. 3 is on, temporarily substitute known good A/C-heater control panel. If solenoid No. 3 is off, temporarily substitute known good programmer. Retest system.
4. Unplug programmer vacuum connector, located under right side of instrument panel. Perform vacuum tests as specified. (Scheme 6) If vacuum tests are as specified, temporarily substitute known good programmer. Retest system. If a port holds vacuum but air does not flow from outlet, inspect associated valve.

Scheme 6

REMOVAL & INSTALLATION

Disconnect negative battery cable. Remove control panel trim plate. Remove screws. Pull A/C-heater control panel outward for access. Unplug connectors. Remove A/C-heater control panel. To install, reverse removal procedure.

1. Disconnect negative battery cable. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Disconnect accumulator inlet and outlet lines. Unplug all electrical connections. Remove pressure cycling switch.
2. Remove accumulator. Measure and discard refrigerant oil. Add same amount of clean refrigerant oil as was drained. To install, reverse removal procedure. Use new "O" rings lubricated with clean refrigerant oil. Evacuate and recharge system.

Disconnect battery ground cable. Unplug blower motor connector. Remove blower motor. To install, reverse removal procedure.

Disconnect negative battery cable. Remove rear sight shield. Disconnect positive battery booster cable. Disconnect underhood fuse blocks and all relays. Remove relay bracket. Unplug connector at module. Remove blower motor control module. (Scheme 7) To install, reverse removal procedure.

Scheme 7

1. Disconnect negative battery cable. Discharge A/C system using approved refrigerant recovery/recycling equipment. Remove compressor drive belt. Remove front upper compressor mounting bolt. Raise and support vehicle. From underneath vehicle, remove A/C compressor splash shield. Unplug electrical connectors from compressor.
2. Remove bolt retaining refrigerant lines to compressor. Remove compressor. Measure and discard refrigerant oil. Add same amount of clean refrigerant oil as was drained. To install, reverse removal procedure. Evacuate, recharge, and test system.

1. Remove battery. Discharge A/C system using approved refrigerant recovery/recycling equipment. Remove air cleaner bracket screw. Remove and plug transmission cooler lines (if equipped). Remove upper radiator panel. Disconnect condenser inlet and outlet lines.
2. Remove condenser mounting brackets and upper insulators. Tilt condenser toward radiator and pull upward to remove. Measure and discard refrigerant oil. Add same amount of clean refrigerant oil as was drained. To install, reverse removal procedure. Evacuate, recharge, and test system.

1. Disconnect negative battery cable. Discharge A/C system using approved refrigerant recovery/recycling equipment. Remove accumulator. See ACCUMULATOR. Remove blower control module and blower motor. See BLOWER MOTOR and BLOWER MOTOR CONTROL MODULE. Remove vacuum reservoir.
2. Remove evaporator tube. Remove brackets and heat shield from blower module. Cut insulation along indicated line. Remove evaporator. Measure and discard refrigerant oil. Add same amount of clean refrigerant oil as was drained. To install, reverse removal procedure. Evacuate, recharge, and test system.

Disconnect negative battery cable. Drain engine cooling system. Remove heater hoses from heater core fittings. Remove heater core cover screws and heater core cover. Remove heater core. To install, reverse removal procedure.

Removal

High pressure cut-off switch is located at rear of compressor. Disconnect negative battery cable. Discharge A/C system using approved refrigerant recovery/recycling equipment. Raise and support vehicle. Unplug switch electrical connector. Using snap ring pliers, remove switch retainer. Withdraw switch from rear head of compressor. Remove and discard "O" ring.

Installation

Coat new "O" ring with refrigeration oil. Install "O" ring into switch cavity groove. Coat new switch with refrigeration oil. Install switch into switch cavity. Install switch retainer and electrical connector. Lower vehicle. Evacuate, recharge, and test system.

Sensor is located behind center of instrument panel, at end of aspirator duct. (Scheme 8) Remove instrument panel lower trim plate. Remove air vent deflectors. Remove glove box. Remove bolts, screws and instrument panel trim plate. Disengage snap tabs from aspirator duct. Remove connector and sensor. To install, reverse removal procedure. Ensure foam on instrument panel lower trim plate tube is in good condition and makes good seal.

Scheme 8

1. Orifice tube is located in line between condenser and evaporator. Discharge A/C system using approved refrigerant recovery/recycling equipment. Disconnect condenser outlet fitting. Disconnect evaporator inlet fitting. Remove A/C refrigerant line clamp.
2. Using Orifice Tube Remover (J-26549-D), remove orifice tube. To install, insert new orifice tube with short screen toward condenser. To complete installation, reverse removal procedure. Evacuate, recharge, and test system.

Sensor is located at front center of car, on side of radiator center brace. Remove upper grille reveal molding. Unplug electrical connector from sensor. Remove sensor. To install, reverse removal procedure.

Disconnect negative battery cable. Pressure cycling switch is mounted on a Schrader-type valve at accumulator; discharging system is not necessary. Unplug pressure cycling switch electrical connector. Unscrew switch. Remove "O" ring. Coat new "O" ring with refrigeration oil. To complete installation, reverse removal procedure.

1. Disconnect negative battery cable. Carefully pry out instrument panel lower trim plate. Remove air vent deflector. Remove glove compartment, right courtesy light and oil life module (if equipped). Remove right sound insulator.
2. Unplug electrical and vacuum connectors. Remove driver air mix valve link. Remove bolts. Slide programmer from tabs. To install, reverse removal procedure. Adjust programmer links. See AIR MIX VALVE under ADJUSTMENTS.

Removal & Installation (Left Side)

Solar sensor is located at top of instrument panel, near left radio speaker. Pry up left and right reveal covers. Remove retaining bolts and upper trim panel. Remove left speaker. Rotate sensor 1/4 turn to release from mounting. Pull sensor through speaker opening. Unplug connector. (Scheme 9) To install, reverse removal procedure.

Removal & Installation (Right Side)

Sensor is located at top of instrument panel, near right radio speaker. Carefully pry out lower instrument panel trim plate. Remove glove box. Rotate sensor 1/4 turn to release from mounting. Unplug connector. (Scheme 9) To install, reverse removal procedure.

Scheme 9

Automatic A/C-Heater System Wiring Diagram (1 Of 2). Scheme 10

Automatic A/C-Heater System Wiring Diagram (2 Of 2). Scheme 11

See also:
• A/C-HEATER SYSTEM - MANUAL
• A/C COMPRESSOR CLUTCH CONTROLS
• DIAGNOSTIC TROUBLE CODE (DTC)
• TESTING
• CLEARING CODES
• AIR MIX VALVE