Engine, A/T Controls - Harsh 2-1 Downshift
T-SB-0166-10June 29, 2010
ECM Calibration: Enhancement to Shifting Performance
Service Category
Drivetrain
Section
Automatic Transmission/Transaxle
Market
USA
Applicability
Introduction
Some vehicles may exhibit a harsh shift on acceleration below 20 mph during the 2-1 downshift on vehicles equipped with an A750 transmission. The Engine Control Module/ECM (SAE term: Powertrain Control Module/PCM) calibration has been revised. Use the following repair procedure to address this condition.
Production Change Information
This TSB applies to vehicles produced BEFORE the Production Change Effective VINs shown.
Warranty Information
APPLICABLE WARRANTY
^ This repair is covered under the Toyota Federal Emission Warranty. This warranty is in effect for 96 months or 80,000 miles, whichever occurs first, from the vehicle's in-service date.
^ Warranty application is limited to occurrence of the specified condition described in this bulletin.
Parts Information
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 the Materials Distribution Center (MDC) through Dealer Daily - Dealer Support Materials Orders.
Calibration Information
Required Tools & Equipment
Repair Procedure
1. Test drive the vehicle and confirm there is a harsh shift on acceleration below 20 mph.
NOTE
If there is NO harsh shift felt below 20 mph, this TSB does NOT apply. Continue diagnosis per the Repair Manual to isolate the cause of the condition.
2. Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 1 or 2. 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 located on the Technical Information System (TIS), Diagnostics - Battery.
Follow the procedures outlined in TSB No. T-SB-0064-10, "Techstream ECU Flash Reprogramming Procedure� and flash the ECM (PCM) with the NEW calibration file update.
4. Start the engine and warm it up to normal operating temperature before test driving.
5. Test drive the vehicle to confirm proper vehicle operation and ECM (PCM) initial learning.
Refer to the Technical Information System (TIS) applicable model and model year Repair Manual:
^ 2010 4Runner:
Drivetrain - Automatic Transmission/Transaxle - "A750E / A750F Automatic Transmission/Transaxle: Automatic Transmission System: Initialization"
^ 2010 FJ Cruiser:
Drivetrain - Automatic Transmission/Transaxle - "A750E / A750F Automatic Transmission: Automatic Transmission System: Initialization"
6. Install the Authorized Modifications Label.
A. Using a permanent marker enter the following information on the label:
^ ECM part number [Refer to the Parts In formation 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 or 2. The Authorized Modifications Label is available through the MDC P/N 00451-00001-LBL.
7. Test drive the vehicle to confirm proper vehicle operation.