NO.3 NO TEMPERATURE CONTROL WITH CLIMATE CONTROL UNIT


id070300802400

3

No temperature control with climate control unit.

DESCRIPTION

• 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, wire clamp malfunction
• Climate control unit rack-and-pinion, air mix wire malfunction
• A/C unit air mix door malfunction
• Heater piping malfunction

Diagnostic procedure

Step

Inspection

Inspection item (s)

1

INSPECT COOLANT TEMPERATURE

• Is coolant sufficiently warmed up?
Yes
Go to next step.
No
Warm engine up, then go to Step 8.
2

INSPECT A/C UNIT AIR MIX SYSTEM

• Inspect A/C unit air mix links, air mix cranks, air mix rods or 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 above items normal?
Yes
Go to next step.
No
Apply grease or install links, cranks, and rods securely in their proper positions, repair or replace wire clamp, then go to Step 8.
3

VERIFY THAT AIR MIX WIRE FROM A/C UNIT IS POSITIONED SECURELY AND CORRECTLY (IF AVAILABLE)

• Is air mix wire securely installed in the correct position in relation to A/C unit air mix links?
Yes
Go to next step.
No
Adjust air mix wire or install securely in correct position, then go to Step 8.
4

INSPECT CLIMATE CONTROL UNIT

• Inspect climate control unit as follows.
- Is bevel gear set propely engaged?
- Is air mix wire properly installed in correct position in relation to bevel gear?
- Is wire clamp free of deformation?
• Are above items okay?
Yes
Go to next step.
No
Propely engage bevel gear or install air mix wire in correct position, repair or replace wire clamp, then go to Step 8.
5

INSPECT A/C UNIT

• Is there any foreign material or obstruction in A/C unit air mix doors?
Yes
Remove obstruction, then go to Step 8.
No
Go to next step.
6

INSPECT A/C UNIT AIR MIX DOORS

• Is A/C unit air mix door securely and properly installed?
Yes
Inspect air mix door for cracks or damage, then go to next step.
No
Install air mix door securely in proper position, then go to next step.
7

INSPECT HEATER LINES

• Inspect heater lines.
- Is heater piping free of damage and cracks?
- Are heater piping connections free of engine coolant leakage?
- Are heater piping connections securely tightened?
- Are heater piping installation points on A/C unit free of engine coolant leakage?
• Are above items normal?
Yes
Operation is normal. Recheck malfunction symptoms.
No
If heater piping connections is loosed, tighten connections with specified torque.
Repair or replace heater piping, then go to next step.
8

VERIFY THAT MALFUNCTION SYMPTOM OCCURS AFTER REPAIR

• Does unit operate in every temperature setting?
Yes
Troubleshooting completed.
Explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.