NO TEMPERATURE CONTROL WITH CLIMATE CONTROL UNIT [CLIMATE CONTROL SYSTEM]

DESCRIPTION	• Temperature does not change when operating temperature dial • Malfunction in A/C unit and/or climate control unit air mix system • Malfunction in air mix actuator or related wiring harness
POSSIBLE CAUSE	• INTERIOR 15 A, ROOM 25 A fuse malfunction • Open or short circuit in wiring harness between fuse block and climate control unit • Open or short circuit in wiring harness between climate control unit and air mix actuator • Air mix actuator malfunction • Air mix gear malfunction • Air mix door malfunction • Climate control unit malfunction • Heater hose malfunction

• When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors while performing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions.

If there is a problem, check to make sure connectors, terminals and wiring harnesses are connected correctly and undamaged.

Step	Inspection		Action
1	INSPECT COOLANT TEMPERATURE • Is the coolant sufficiently warmed up?	Yes	Go to the next step.
1		No	Warm up the engine, then go to Step 19.
2*	INSPECT FUSE • Remove the INTERIOR 15 A fuse and ROOM 25 A fuse. • Is the fuse normal?	Yes	Go to the next step.
2*		No	If the fuse is melted: Repair or replace wiring harness for short to ground and replace the fuse. If the fuse is deterioration: Replace the fuse. Then go to Step 19.
3*	INSPECT TO SEE WHETHER MALFUNCTION (OPEN CIRCUIT) IS IN B+ SIGNAL WIRING HARNESS (BETWEEN FUSE BLOCK AND CLIMATE CONTROL UNIT) OR ELSEWHERE • Disconnect the climate control unit connector. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) • Switch the ignition ON (engine off or on). • Measure voltage at the following terminal of climate control unit. ― Terminal L • Is the voltage approx. 12 V?	Yes	Go to the next step.
3*		No	Refer to the wiring diagram and verify whether or not there is a common connector between fuse block terminal and climate control unit terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open circuit. Go to Step 19.
4*	INSPECT TO SEE WHETHER MALFUNCTION IS IN CLIMATE CONTROL UNIT OR AIR MIX ACTUATOR • Switch the ignition off. • Reconnect the disconnected climate control unit connector. • Switch the ignition ON (engine off or on). • Measure voltage at the following terminals of climate control unit when temperature setting to MAX HOT and MAX COLD. ― Terminal G • Is voltage normal?	Yes	Go to Step 15.
4*		No	Go to the next step.
5*	INSPECT TO SEE WHETHER MALFUNCTION IS IN POSITION SENSOR OR ELSEWHERE • Measure voltage at the following terminal of climate control unit when airflow mode at VENT and DEFROSTER. ― Terminal I • Is voltage normal?	Yes	Go to Step 8.
5*		No	Go to the next step.
6*	INSPECT TO SEE WHETHER MALFUNCTION (LACK OF CONTINUITY OR SHORT TO BATTERY POWER OR GROUND) IS IN POSITION SENSOR POWER SUPPLY OR ELSEWHERE • Measure voltage at the following terminal of climate control unit. ― Terminal H • Is voltage approx. 5 V?	Yes	Go to the next step.
6*		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness. Go to Step 19.
7*	INSPECT TO SEE WHETHER MALFUNCTION (LACK OF CONTINUITY OR OPEN) IS IN POSITION SENSOR GROUND OR ELSEWHERE • Measure voltage at the following terminal of climate control unit. ― Terminal E • Is the voltage below. 1.0 V?	Yes	Go to Step 11.
7*		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness. Go to Step 19.
8	INSPECT TO SEE WHETHER MALFUNCTION (SHORT TO POWER SUPPLY) IS IN WIRING HARNESS (AIR MIX POSITION SIGNAL) OR ELSEWHERE • Measure voltage at the following terminals of climate control unit. ― Terminal G • Is the voltage approx. 12V, at Step 4?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to power supply. Go to Step 19.
8		No	Go to the next step.
9*	INSPECT TO SEE WHETHER MALFUNCTION (LACK OF CONTINUITY) IS IN WIRING HARNESS (AIR MIX POSITION SIGNAL) OR ELSEWHERE • Switch the ignition off. • Disconnect the climate control unit connector. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) • Disconnect the air mix actuator connector. (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) • Verify continuity at following terminals between climate control unit and air mix actuator. ― Terminal G —Terminal E • Is there continuity?	Yes	Go to the next step.
9*		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and each side air mix actuator terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness. Go to Step 19.
10*	INSPECT TO SEE WHETHER MALFUNCTION (SHORT TO GROUND) IS IN WIRING HARNESS (AIR MIX POSITION SIGNAL) OR POSITION SENSOR COMMON (POWER SUPPLY OR GROUND) HARNESS • Climate control unit and air mix actuator connectors disconnected. • Verify continuity at the following terminals between climate control unit and ground. ― Terminal G • Is there continuity?	Yes	Repair wiring harness for short to ground between climate control unit and air mix actuator. Then go to Step 19.
10*		No	Inspect and repair for open circuit following: • Between air mix actuator terminal D and junction point to airflow mode actuator (position sensor power supply). • Between air mix actuator terminal F and junction point to airflow mode actuator (position sensor ground). Then go to Step 19.
11*	INSPECT TO SEE WHETHER MALFUNCTION (LACK OF CONTINUITY) IS IN AIR MIX ACTUATOR OR WIRING HARNESS (BETWEEN CLIMATE CONTROL UNIT AND AIR MIX ACTUATOR) • Disconnect the air mix actuator connector. (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) • Switch the ignition ON (engine off or on). • Measure voltage at the following terminals of air mix actuator. ― Terminal W (COLD motor drive signal) ― Terminal X (HOT motor drive signal) • Are voltages as shown below? ― COLD motor drive signal: approx. 10 V during COLD and below 1.0 V during HOT ― HOT motor drive signal: below 1.0 V during COLD and approx. 10 V during HOT	Yes	Go to Step 15.
11*		No	Go to the next step.
12*	INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO B+ BETWEEN CLIMATE CONTROL UNIT AND AIR MIX ACTUATOR) OR ELSEWHERE • Air mix actuator connectors disconnected. • Disconnect the climate control unit connector. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) • Switch the ignition ON (engine off or on). • Measure voltage at the following terminals of the climate control unit harness-side connector. ― Terminal W (COLD motor drive signal) ― Terminal X (HOT motor drive signal) • Are voltages approx. 0 V?	Yes	Go to the next step.
12*		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to power supply. Go to Step 19.
13*	INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (SHORT TO GROUND BETWEEN CLIMATE CONTROL UNIT AND AIR MIX ACTUATOR) OR ELSEWHERE • Climate control unit and air mix actuator connectors are disconnected. • Switch the ignition off. • Verify that continuity at the following harness-side connector terminals between climate control unit and ground. ― Terminal W (COLD motor drive signal) ― Terminal X (HOT motor drive signal) • Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to ground. Go to Step 19.
13*		No	Go to the next step.
14*	INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (LACK OF CONTINUITY OR OPEN BETWEEN CLIMATE CONTROL UNIT AND AIR MIX ACTUATOR) OR ELSEWHERE • Climate control unit and air mix actuator connectors are disconnected. • Switch the ignition off. • Verify that continuity at the following harness-side connector terminals between climate control unit and air mix actuator. L.H.D. ― Terminal A—climate control unit terminal W (COLD motor drive signal) ― Terminal B—climate control unit terminal X (HOT motor drive signal) R.H.D. ― Terminal B—climate control unit terminal W (COLD motor drive signal) ― Terminal A—climate control unit terminal X (HOT motor drive signal) • Is there continuity?	Yes	Go to the next step.
14*		No	Refer to the wiring diagram and verify whether or not there is a common connector between climate control unit terminal and air mix actuator terminal. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness. Go to Step 19.
15	INSPECT AIR MIX ACTUATOR • Inspect the air mix actuator. (See AIR MIX ACTUATOR INSPECTION [FULL-AUTO AIR CONDITIONER].) (See AIR MIX ACTUATOR INSPECTION [MANUAL AIR CONDITIONER].) • Is air mix actuator normal?	Yes	Go to the next step.
15		No	Replace the air mix actuator. Then go to 19. (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See AIR MIX ACTUATOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
16	INSPECT AIR MIX GEAR • Inspect the air mix gears for each-side. (See A/C UNIT REMOVAL/INSTALLATION.) ― Is grease on gear? ― Is gear securely and properly installed? ― Is gear free of obstructions and hindrances? • Are the above items normal?	Yes	Go to the next step.
16		No	Apply grease to gear. If any gear is damaged. Replace malfunctioning part. (See A/C UNIT DISASSEMBLY/ASSEMBLY.) Then go to Step 19.
17	INSPECT TO SEE WHETHER MALFUNCTION IS IN CLIMATE CONTROL UNIT OR AIR MIX DOOR ELSEWHERE • Inspect the A/C unit and each-side air mix door. (See A/C UNIT REMOVAL/INSTALLATION.) ― Is door free of obstructions and damage? ― Are doors securely and properly installed? • Are the above items normal?	Yes	Go to the next step.
17		No	Remove the obstruction, or install door in proper position. If any doors are cracked, replace them. (See A/C UNIT DISASSEMBLY/ASSEMBLY.) Then go to the next step.
18	INSPECT HEATER HOSE • Inspect the heater hoses for the following: ― Is heater hoses free of damage and cracks? ― Are heater hoses connections free of engine coolant leakage? ― Are heater hoses installation points on A/C unit free of engine coolant leakage? • Are the above items normal?	Yes	Replace the climate control unit. Then go to the next step. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
18		No	If heater hoses connections are loose, install securely in the correct position. Repair or replace the heater hoses. (See HEATER HOSE REMOVAL/INSTALLATION.) Then go to the next step.
19	VERIFY THAT MALFUNCTION SYMPTOM DOES NOT RECUR AFTER REPAIR • Does the unit operate at every temperature setting?	Yes	Troubleshooting completed. Explain repairs to customer.
19		No	Recheck malfunction symptoms, then repeat from Step1 if the malfunction recurs.