Canada - A/C - Side To Side Temperature Variation
BulletinL-TCI-2964
Issue Date
August 24, 2011
Title:
HEATER CORE RESTRICTION
Service Category
Vehicle Interior
Section
Heating/Air Conditioning
Market
Canada
APPLICABILITY:
INTRODUCTION:
Some 2008 - 2010 model year RX350, 2008 model year RX400h, and 2010 model year RX450h vehicles may exhibit a variation greater than 11°C (20°F) in HVAC vent temperatures between the driver and passenger side when heat is utilized at the same temperature setpoint.
Use the following repair procedure to address this condition.
WARRANTY INFORMATION:
REQUIRED TOOLS & EQUIPMENT:
PARTS INFORMATION:
RX350:
RX400h:
RX450h:
REPAIR PROCEDURE:
1. Using a thermometer, confirm the condition matches the Introduction.
2. Inspect for corrosion sediment under the radiator cap and in the bottom of the radiator reserve tank.
- If corrosion sediment is found - Continue to step 3.
- If no corrosion is found - Refer to the Technical Information System (TIS), applicable model and model year Repair Manual: Vehicle Interior - Heating/Air Conditioning - "Air Conditioning System: Air Conditioning System: Problem Symptoms Table".
3. Drain all coolant from the radiator and reserve tank and close the radiator drain. Thoroughly rinse the reserve tank and pick-up tube with water and reinstall.
4. Remove the thermostat from its housing and reassemble the housing.
IMPORTANT
This will allow the cleaning solution to circulate without first requiring the engine to reach operating temperature.
Refer to the Technical Information System (TIS), applicable model and model year Repair Manual: Engine/Hybrid System - Cooling - "2GR-FE Cooling: Thermostat: Removal"
- 2008 / 2009 / 2010 RX350
- 2008 RX400h
- 2010 RX450h
5. Install a cooling system flush adapter between the heater core inlet and outlet hoses, bypassing the heater core.
6. Install a radiator neck fill adapter (not the funnel) and install a hose of equal diameter into neck adapter. Ensure length is sufficient for your selected drain location.
NOTE
Selected drain must be direct to coolant waste or a pan/receptacle that can be transferred to coolant waste.
7. Install a fresh water hose onto the cooling system flush adapter.
8. Turn on the water and then start the engine and allow to idle. Continue to flush with a minimum of 95 liters (25 gallons) of water to completely flush the system.
9. Turn off the engine and the fresh water supply.
10. Install the cap over the fresh water inlet on the adapter.
11. Drain water from the radiator and then close the radiator drain.
12. Create a 10% citric acid solution by mixing 900 grams of citric acid powder with water in a clean 1 gallon container until well dissolved.
13. Fill the cooling system through the radiator neck with the citric acid solution. Add water to fill the cooling system.
14. Start the engine and allow to idle for 30 minutes.
15. Drain the citric acid solution from the radiator and close the drain.
16. Perform steps 6 - 15 again.
17. Perform steps 6 - 9 again.
18. Remove the cooling system flush adapter, then replace the heater core, radiator, water inlet housing, water inlet, water outlet, bypass pipe, ATF cooler (if applicable), seals, and gaskets for your vehicle as listed in the Parts Information section and reinstall the thermostat in the housing.
Then proceed to step 19 at the end of this bulletin.
For parts replacement, refer to TIS, applicable model and model year Repair Manual:
RX 350:
- Radiator:
Engine/Hybrid System - Cooling - "2GR-FE Cooling: Radiator:
- 2008 RX350: Removal / Installation"
- 2009 RX350: Removal / Installation"
- 2010 RX350: Removal / Installation"
- Inlet Pipe/Thermostat:
Engine/Hybrid System - Cooling - "2GR-FE Cooling: Thermostat:
- 2008 RX350: Removal / Installation"
- 2009 RX350: Removal / Installation"
- 2010 RX350: Removal / Installation"
- Water Outlet/Bypass Pipe:
Engine/Hybrid System - Cooling - "2GR-FE Cooling: Water Pump:
- 2008 RX350: Removal / Installation"
- 2009 RX350: Removal / Installation"
- 2010 RX350: Removal / Installation"
- Heater Core:
Vehicle Interior - Heating/Air Conditioning - "Air Conditioning: Air Conditioning Unit:
- 2008 RX350: Removal / Installation"
- 2009 RX350: Removal / Installation"
- 2010 RX350: Removal / Installation"
- Oil Cooler:
Engine/Hybrid System - Lubrication - "2GR-FE Lubrication: Engine Oil Cooler (w/Oil Cooler):
- 2008 RX350: Removal / Installation"
- 2009 RX350: Removal / Installation"
- 2010 RX350: Removal / Installation"
RX 400h:
- Radiator:
Engine/Hybrid System - Cooling - "3MZ-FE Cooling: Radiator:
- 2008 RX400h: Removal / Installation"
- Inlet Pipe/Thermostat:
Engine/Hybrid System - Cooling - "3MZ-FE Cooling: Thermostat:
- 2008 RX400h: Removal / Installation"
- Water Outlet/Bypass Pipe:
Engine/Hybrid System - Cooling - "3MZ-FE Cooling: Water Pump:
- 2008 RX400h: Removal / Installation"
- Heater Core:
Vehicle Interior - Heating/Air Conditioning - "Air Conditioning: Air Conditioning Unit:
- 2008 RX 400h: Removal / Installation"
RX450h:
- Radiator:
Engine/Hybrid System - Cooling - "2GR-FXE Cooling: Radiator:
- 2010 RX450h: Removal / Installation"
- Inlet Pipe/Thermostat:
Engine/Hybrid System - Cooling - "2GR-FXE Cooling: Thermostat:
- 2010 RX450h: Removal / Installation"
- Water Outlet/Bypass Pipe:
Engine/Hybrid System - Cooling - "2GR-FXE Cooling: Water Pump:
- 2010 RX450h: Removal / Installation"
- Heater Core:
Vehicle Interior - Heating/Air Conditioning - "Air Conditioning: Air Conditioning Unit:
- 2010 RX450h: Removal / Installation"
- Oil Cooler:
Engine/Hybrid System - Lubrication - "2GR-FXE Lubrication: Engine Oil Cooler (w/Oil Cooler):
- 2010 RX450h: Removal / Installation"
19. Fill the system with the required coolant amount.
20. Confirm proper vehicle operation.
NOTE:
Issue of this Technical Service Bulletin is to ensure that proper repair information is available.
IT DOES NOT CONSTITUTE AN AUTHORIZATION FOR REPAIR. Normal provisions of the formal warranty policy, as applicable, will apply.