NO TEMPERATURE CONTROL WITH CLIMATE CONTROL UNIT [MANUAL AIR CONDITIONER]


id0703c2700600

DESCRIPTION
•  Temperature does not change when operating temperature setting dial
•  Malfunction in A/C unit and/or climate control unit air mix system
POSSIBLE CAUSE
•  Air mix wire malfunction
•  Air mix link malfunction
•  Air mix door malfunction
•  Climate control unit malfunction
•  Heater hose malfunction


Diagnostic Procedure

Step

Inspection

Action

1
INSPECT COOLANT TEMPERATURE
•  Is the coolant sufficiently warmed up?
Yes
Go to the next step.
No
Warm up the engine, then go to Step 8.
2
INSPECT A/C UNIT AIR MIX SYSTEM
•  Inspect the A/C unit air mix links, air mix cranks, and wire clamp.
―  Is there grease on links and cranks?
―  Are links and cranks securely installed in their proper positions?
―  Is wire clamp free of deformation?
•  Are the above items normal?
Yes
Go to the next step.
No
Apply grease or install the links, cranks, and rods securely in their proper positions, repair or replace the wire clamp, then go to Step 8.
3
VERIFY THAT AIR MIX WIRE FROM A/C UNIT IS POSITIONED SECURELY AND CORRECTLY
•  Is the air mix wire securely installed in the correct position in relation to the A/C unit air mix links?
Yes
Go to the next step.
No
Adjust the air mix wire or install securely in the correct position, then go to Step 8.
4
INSPECT CLIMATE CONTROL UNIT
•  Inspect the climate control unit.
•  Is the climate control unit normal?
Yes
Go to the next step.
No
Replace the climate control unit, then go to Step 8.
5
INSPECT AIR MIX LINK
•  Inspect the air mix link.
―  Is grease on link?
―  Are links securely and properly installed?
―  Are links free of obstructions and hindrances?
•  Are the above items normal?
Yes
Go to the next step.
No
Apply grease to links.
If any links are damaged. Replace malfunctioning part.
Then go to Step 8.
6
INSPECT A/C UNIT AIR MIX DOOR
•  Inspect the air mix door.
―  Is door free of obstructions and damage?
―  Are doors securely and properly installed?
•  Are the above items normal?
Yes
Go to the next step.
No
Remove the obstruction, or install door in proper position.
If any doors are cracked, replace them.
Then go to the next step.
7
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
Go to the next step.
No
If heater hoses connections are loose, install securely in the correct position.
Repair or replace the heater hoses.
Then go to the next step.
8
VERIFY THAT MALFUNCTION SYMPTOM OCCURS AFTER REPAIR
•  Does the unit operate in every temperature setting?
Yes
Troubleshooting completed.
Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if the malfunction recurs.