Engine Controls - Vibration Felt Between 30 and 75 MPH
L-SB-0013-12March 14, 2012
Vibration Between 30 - 75 MPH
Service Category
Drivetrain
Section
Automatic Transmission/Transaxle
Market
USA
Applicability
Introduction
Some 2009 - 2012 model year LS 460 vehicles equipped with 4WD may exhibit a vibration or shudder feeling between 30 - 75 mph (48 - 121 km/h). The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has been revised to address this condition. Follow the procedure in this bulletin to determine if recalibration of the ECM (PCM) is required.
Parts Information
Warranty Information
Calibration Information
Required Tools & Equipment
Repair Procedure
1. Test drive the vehicle and confirm a vibration or shudder feeling is felt throughout the vehicle between 30 - 75 mph (48 - 121 km/h).
2. Perform a test drive with Techstream take a snapshot and place a flag when the condition is occurring.
3. Review the snapshot and confirm the following conditions (see Figure 1).
A. Is the vehicle speed between 30 - 75 mph (48 - 121 km/h) when the condition occurred?
^ YES - Continue to next question.
^ NO - This bulletin does NOT apply continue diagnosis per the Repair Manual.
B. Is the vehicle in 7th or 8th gear when the condition occurred?
^ YES - Continue to next question.
^ NO - This bulletin does NOT apply continue diagnosis per the Repair Manual.
C. Is torque converter lock-up ON when the condition occurred?
^ YES - Continue to step 4.
^ NO - This bulletin does NOT apply continue diagnosis per the Repair Manual.
4. Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 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 5.
5. 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 Instruction Manual located on the Technical Information System (TIS), Diagnostics - Tools & Equipment - Battery Diagnostics.
Follow the procedures outlined in Service Bulletin L-SB-0015-10, "Techstream ECU Flash Reprogramming Procedure", and flash the ECM (PCM) with the NEW calibration file update.
6. Start the engine and warm it up to normal operating temperature before test driving.
7. Perform Automatic Transmission initialization and test drive the vehicle to confirm proper vehicle operation.
Refer to the Technical Information System (TIS) applicable model year LS 460 Repair Manual:
^ 2009 / 2010 / 2011 / 2012 LS 460:
Drivetrain - Automatic Transmission/Transaxle - "AA80F Automatic Transmission: Automatic Transmission System: Initialization"
8. Install the Authorized Modifications Label.
A. Using a permanent marker enter the following information on the label:
^ ECM 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 bulletin number]
B. Affix the Authorized Modifications Label to the vehicle at the location shown in Figure 2. The Authorized Modifications Label is available through the MDC P/N 00451-00001-LBL.