Canada - A/C - Poor Heater Performance When Cold

Bulletin
TSB3340

Issue Date
August 18, 2010

Market
Canada

Title
HEATER PERFORMANCE

Component
HEATING/ AIR CONDITIONING

Models
'08 Sequoia; '07-'08 Tundra

INTRODUCTION:
Some 2008 model year Sequoia and 2007 - 2008 model year Tundra vehicles may exhibit reduced cold-start heater warm-up performance in cold conditions. A newly designed Engine Control Module/ECM (SAE term: Powertrain Control Module/PCM) logic is available to address this condition.
Use the following repair procedure to recalibrate the ECM (PCM).






APPLICABILITY:






WARRANTY INFORMATION:


PRODUCTION CHANGE INFORMATION:







This TSB applies to vehicles produced BEFORE the Production Change Effective VIN shown.






REQUIRED TOOLS & EQUIPMENT:


PARTS INFORMATION:






Sequoia & Tundra:






2008 Sequoia:






2007 Tundra:






2008 Tundra:

NOTE:
- The ECM (PCM) should NOT be replaced as part of the repair procedure.
- Authorized Modification Labels may be ordered in packages of 25 from your facing PDC.

CALIBRATION INFORMATION:






2008 Sequoia:






2007 Tundra:






2008 Tundra:

REPAIR PROCEDURE:
1. Confirm the condition matches the Introduction.







2. Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 1. Confirm if the ECM (PCM) calibration has been updated. If the calibration ID listed is NOT the latest ECM (PCM) calibration - go to step 3.
3. Flash Reprogram the ECM (PCM).

NOTE:
- The GR8 Battery Diagnostic Station MUST be used in Power Supply Mode to maintain battery voltage at 13.5 volts while flash reprogramming the vehicle.
- For details on how to use the GR8 Battery Diagnostic Station, refer to the GR8 Battery Diagnostic Station Instruction Manual located on ETAS/TIS library > Tools > tools and equipment > GR8 Battery Diagnostic Station Instruction Manual.

Follow the procedures outlined in TSB No. 2758, "Techstream ECU Flash Reprogramming Procedure", and flash the ECM (PCM) with the NEW calibration file update.

4. Install the Authorized Modifications Label.
A. Using a permanent marker, enter the following information on the label:
- ECU part number [Refer to the Parts Information section for the CURRENT PART NUMBER]
- Calibration ID(s) [Refer to the Calibration Identification Chart for the NEW CALIBRATION ID]
- Dealer Code
- Repair Date
- Change Authority [This TSB number]

B. Affix the Authorized Modifications Label to the vehicle at the location shown in Figure 1. The Authorized Modifications Label is available through your facing PDC, P/N 00451- 00001-25.

5. Test drive the vehicle to 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.