TROUBLE SHOOTING
| CAUTION | Radio is equipped with anti-theft circuitry. Before disconnecting battery, obtain code from owner. After servicing, turn on radio. When the word CODE is displayed, enter 5-digit code to restore operation. |
SELF-DIAGNOSTICS
| CAUTION | Radio is equipped with anti-theft circuitry. Before disconnecting battery, obtain code from owner. After servicing, turn on radio. When the word CODE is displayed, enter 5-digit code to restore operation. |
ENTERING SELF-DIAGNOSTICS
- Turn ignition switch to ON position. Set temperature control dial to maximum cooling, then slowly to maximum hot. After one minute, press AUTO and then the OFF button. Simultaneously press AUTO and OFF buttons.
- If any problem exists in the system when the buttons are depressed, the temperature indicator will light up the segment corresponding to the error code. The temperature indicator will then alternate every second between displaying "88" (all segments lit) and the diagnostic trouble code segment. (Scheme 4) If system is okay, segments will not light up.
Note. Fault information is not retained in memory. In case of multiple problems, appropriate indicator lights will light up. If indicator lights "A","C","E","G","I" and "L" light up at same time, common ground for sensors may be open.
EXITING SELF-DIAGNOSTICS
To exit self-diagnostics at any time, turn ignition switch to OFF position. This will clear trouble codes.
Scheme 4
| Indicator Segment | (1) Component |
|---|---|
| "A" | In-Car Temperature Sensor Open |
| "B" | In-Car Temperature Sensor Short |
| "C" | Outside (Ambient) Temperature Sensor Open |
| "D" | Outside (Ambient) Temperature Sensor Short |
| "E" | Sunlight Sensor Open |
| "F" | Sunlight Sensor Short |
| "G" | Evaporator Temperature Sensor Open |
| "H" | Evaporator Temperature Sensor Short |
| "I" | Air Mix Control Motor Open |
| "J" | Air Mix Control Motor Short |
| "K" | Air Mix Control Motor Mechanical Failure |
| "L" | Mode Control Motor Open |
| "M" | Mode Control Motor Short |
| "N" | Blower Motor |
| (1) To avoid damaging a sensor, use a DVOM with a measuring current of one milliamp or less. | |
| (1) | To avoid damaging a sensor, use a DVOM with a measuring current of one milliamp or less. |
INDICATOR SEGMENT CORRESPONDING TO DIAGNOSTIC TROUBLE CODES
TESTING
| CAUTION | Radio is equipped with anti-theft circuitry. Before disconnecting battery, obtain code from owner. After servicing, turn on radio. When the word CODE is displayed, enter 5-digit code to restore operation. |
AIR MIX CONTROL MOTOR TESTING
- Disconnect air mix control motor connector. Use a fused jumper wire and connect battery voltage to air mix control motor terminal No. 2. Use a fused jumper wire to ground air mix control motor terminal No. 1. (Scheme 5)
- Motor should cycle and stop at maximum cool position, reverse connections, motor should cycle to maximum heat position (when air mix control motor stops running, immediately disconnect battery power). NOTE: If air mix control motor does not run, remove air mix control motor. Check doors and linkage for smooth operation. If doors and linkage are okay, air mix control motor must be replaced.
- Use a DVOM to measure resistance between air mix control motor connector terminals No. 5 and 7, resistance should be between 4.2-7.8 k/ohms.
- Measure resistance between air mix control motor connector terminals No. 3 and 5. At maximum cooling, resistance should be between.58-1.09 k/ohms. At maximum heating, resistance should be between 3.52-6.55 k/ohms.
Scheme 5
EVAPORATOR TEMPERATURE SENSOR TESTING
Unplug connector from evaporator temperature sensor. Use a DVOM to measure resistance between terminals on sensor. Check readings with the EVAPORATOR TEMPERATURE SENSOR RESISTANCE table.
| Temperature °F (°C) | Ohms |
|---|---|
| 32 (0) | 3000 |
| 50 (10) | 1850 |
| 68 (20) | 1300 |
| 86 (30) | 850 |
EVAPORATOR TEMPERATURE SENSOR RESISTANCE
IN-CAR TEMPERATURE SENSOR TESTING
Remove instrument panel lower cover. Remove sensor from instrument panel. Use a DVOM to measure resistance between terminals on sensor. Vary resistance in sensor by heating and cooling sensor while monitoring resistance readings. Check readings with those in the IN-CAR TEMPERATURE SENSOR RESISTANCE table.
| Temperature °F (°C) | Ohms |
|---|---|
| 32 (0) | 6600 |
| 50 (10) | 4100 |
| 68 (20) | 2500 |
| 86 (30) | 1700 |
| 104 (40) | 1100 |
IN-CAR TEMPERATURE SENSOR RESISTANCE
MODE CONTROL MOTOR TESTING
- Disconnect mode control motor connector. Use a fused jumper wire and connect battery voltage to mode control motor terminal No. 2. Use a fused jumper wire to ground mode control motor terminal No. 1. (Scheme 6)
- Motor should cycle and stop at vent mode, reverse connections, motor should cycle to defrost (when mode control motor stops running, disconnect battery power immediately). NOTE: If mode control motor does not run when jumping terminal No. 1, jump terminal No. 1 again after jumping all others. Mode control motor is okay if it runs after jumping terminal No. 1 again.
- Use a DVOM to check for continuity between terminal No. 7 and terminals No. 3, 4, 5, and 6 while manually cycling motor between vent and defrost. Continuity should be indicated on each terminal momentarily while motor is cycling.
Scheme 6
OUTSIDE AIR TEMPERATURE SENSOR TESTING
Unplug connector from outside air temperature sensor, located behind center of front bumper. Use a DVOM to measure resistance between terminals on sensor. Vary sensor resistance by heating and cooling sensor while monitoring resistance readings. Check readings with OUTSIDE AIR TEMPERATURE SENSOR RESISTANCE table.
| Temperature °F (°C) | Ohms |
|---|---|
| 32 (0) | 6600 |
| 50 (10) | 4100 |
| 68 (20) | 2500 |
| 86 (30) | 1700 |
| 104 (40) | 1100 |
OUTSIDE AIR TEMPERATURE SENSOR RESISTANCE
RECIRCULATION CONTROL MOTOR TESTING
Note. To avoid damaging recirculation control motor, DO NOT reverse power and ground leads.
- Disconnect recirculation control motor connector. Connect battery voltage to recirculation control motor terminal No. 1 and ground terminals No. 5 and 7. (Scheme 7) Recirculation control motor should run smoothly.
- Disconnect terminal No. 5 and 7 from ground. Recirculation control motor should stop at fresh air or recirculated air position. Don't cycle recirculation control motor for an extended period of time.
- If recirculation control motor does not run in step 2), check recirculation control motor doors and linkage for smooth operation. If doors and linkage are okay, replace recirculation control motor.
Scheme 7
SUNLIGHT SENSOR TESTING
Carefully remove sunlight sensor from instrument panel. Turn ignition switch to ON position. Use a DVOM to measure voltage between sunlight sensor connector terminals (Red DVOM lead to White/Red wire terminal; Black lead to Yellow/Green wire terminal). Completely cover sensor from sunlight. Reading should be 3.7 volts or greater. Uncover sensor. Reading should be 3.6 volts or less.
Note. The voltage will not change under artificial light of a flashlight or fluorescent lamp.