Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

SYS.OK|MANUAL.DB● LIVE

HOMESERVICE MANUALSTOYOTA2004CELICA GT, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 330 (AIR CONDITIONING SYSTEM)HEATER CONTROL ASSEMBLYHEATER CONTROL ASSEMBLY INSPECTION

2004 Toyota Celica GT, Standard

Heater Control Assembly Inspection

2004 Toyota Celica GT, StandardSECTION Heater Control Assembly Inspection

WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

Inspect illumination operation :
1. Connect the positive (+) lead from the battery to terminal 5 and negative (-) lead to terminal 10, then check that the illumination lights up.
  If operation is not as specified, check the faulty bulb.
  
  Fig 1: Locating Center Cluster Module Terminals 5 & 10
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Apply the tester as shown in Fig 2 to the test for continuity.
  
  Fig 2: Center Single Bulb For Continuity
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  If continuity exists, replace the heater control.
  
  If no continuity exists, replace the bulb.
Inspect indicator operation :
Connect the positive (+) lead from the battery to terminal 1 and negative (-) lead to terminal 7, then check that the illumination light up.

Fig 3: Testing Indicator Light Operation
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If operation is not as specified, proceed next inspection.
Inspect F/R indicator operation :
Connect the positive (+) lead from the two 1.5 V dry cell batteries to terminal 1 and negative (-) lead to terminal 3, then check that the F/R indicator lights up.

Fig 4: Testing Fresh Air/Recirculated Air Indicator Light
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If operation is as specified, replace the A/C amplifier.

If operation is not as specified, replace the cluster module circuit.
Inspect A/C indicator operation :
Connect the positive (+) lead from the two 1.5 V dry cell batteries to terminals 1 and negative (-) lead to terminal 5, then check that the A/C indicator lights up.

Fig 5: Testing A/C Indicator Light
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If operation is as specified, replace the A/C amplifier.

If operation is not as specified, replace the cluster module circuit.
Inspect MAX. A/C indicator operation .
Connect the positive (+) lead from the two 1.5 V dry cell batteries to terminal 1 and negative (-) lead to terminal 15, then check that the MAX. A/C indicator lights up.

Fig 6: Testing Max Indicator Light
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If operation is as specified, replace the A/C amplifier.

If operation is not as specified, replace the cluster module circuit.
Inspect switch continuity .
Check the continuity between terminals while switch is pressed, as shown in Fig 8.

Fig 7: Testing Fresh Air/Recirculated Air, A/C & Max Switches
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready Tools Free Quote Check Quote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.