NO.4 NO TEMPERATURE CONTROL WITH CLIMATE CONTROL UNIT [MANUAL AIR CONDITIONER]

id0702c2812400

4
No temperature control with climate control unit
DESCRIPTION
•  Temperature does not change when operating temperature dial
•  Malfunction in A/C unit and/or climate control unit air mix system
POSSIBLE CAUSE
•  A/C unit air mix link, air mix crank, air mix rod, air mix wire, or wire clamp malfunction
•  Climate control unit rack-and-pinion, or air mix wire malfunction
•  A/C unit air mix door malfunction
•  Heater piping 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, air mix rods, and wire clamp.
―  Is there grease on links and cranks?
―  Are links, cranks, and rods 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
Repair or replace the climate control unit, then go to Step 8.
5
INSPECT A/C UNIT
•  Is there any foreign material or obstruction in the A/C unit air mix doors?
Yes
Remove obstruction, then go to Step 8.
No
Go to the next step.
6
INSPECT A/C UNIT AIR MIX DOOR
•  Is the A/C unit air mix door securely and properly installed?
Yes
Inspect the air mix door for cracks or damage, then go to the next step.
No
Install the air mix door securely in the proper position, then go to the next step.
7
INSPECT HEATER LINE
•  Inspect the heater lines.
―  Is the heater piping free of damage and cracks?
―  Are the heater piping connections free of engine coolant leakage?
―  Are the heater piping connections securely tightened?
―  Are the heater piping installation points on A/C unit free of engine coolant leakage?
•  Are the above items normal?
Yes
Operation is normal. Recheck malfunction symptoms.
No
If heater piping connections are loose, tighten the connections to the specified torque.
Repair or replace the heater piping, 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.