A/T/Engine Controls - MIL ON, Multiple DTC's, Erratic A/T Shift
L-SB-0008-13
February 20, 2013
AB60F Transmission Clutch/Brake Damage
Service Category
Drivetrain
Section
Automatic Transmission/Transaxle
Market
USA
Applicability
Introduction
Some 2008 - 2011 model year LX 570 vehicles may exhibit a MIL "ON" condition with transmission performance DTCs such as P2714, P0751, P0756, P0761, P0766, P0729, P0781, P0894, P2757, or P0776 and/or abnormal transmission shifting. Revised Engine Control Module/ECM (SAE term:
Powertrain Control Module/PCM) software logic has been developed to address this condition. In some cases, replacement of the automatic transmission may also be required.
NOTE
Confirm correct transmission fluid level by following the procedures in the Repair Manual BEFORE ordering parts or reprogramming the ECM (PCM) since incorrect fluid level can also cause these DTCs.
Warranty Information
Parts Information
Calibration Information
Required Tools & Equipment
Repair Procedure
1. Using Techstream save Freeze Frame data clear DTCs (if set) and perform a test drive.
A. Does the MIL "ON" reoccur with transmission performance DTCs resetting?
Most transmission performance DTCs are two-trip detection logic DTCs. For more information on two-trip detection, refer to TIS Techstream Help.
B. Does the transmission display any transmission shifting issues?
^ YES to A or B - Go to step 2.
^ NO to A and B - Continue test driving the vehicle and try to duplicate the MIL "ON" or abnormal transmission shifting. If unable to duplicate complaint, return the vehicle to the customer. Do NOT attempt to repair the vehicle.
2. Check the transmission for evidence of leakage, and address as necessary.
3. Check the transmission fluid level.
Refer to the Technical Information System (TIS), applicable model and model year Repair Manual:
^ 2008 / 2009 / 2010 / 2011 LX 570:
Drivetrain - Automatic Transmission/Transaxle - 'AB60F Automatic Transmission/Transaxle:
Automatic Transmission Fluid: Adjustment"
NOTE
Incorrectly adjusted fluid level can cause transmission shifting issues and MIL "ON" conditions.
Is the transmission fluid level correct?
^ YES - Go to step 4.
^ NO - Adjust fluid level to correct level, then repeat step 3 to confirm correct fluid level.
4. Does the transmission fluid smell burnt or have a gritty feel from contamination?
NOTE
It is normal for WS transmission fluid to change from a clear red color when new to an opaque brown color with use.
^ YES - Reprogram the ECM (PCM) per steps 5 - 6, then replace the transmission assembly per step 8.
^ NO - Go to step 5.
5. Flash reprogram the ECM (PCM).
A. 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 B.
B. 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 - Tools & Equipment - Battery Diagnostics.
Follow the procedures outlined in Service Bulletin "Techstream ECU Flash Reprogramming Procedure, and flash the ECM (PCM) with the NEW calibration file update.
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 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 1. The Authorized Modifications Label is available through the MDC P/N 00451-00001-LBL.
7. Test drive the vehicle and perform transmission initialization.
Refer to TIS applicable model and model year Repair Manual:
^ 2008 / 2009 / 2010 / 2011 LX 570:
Drivetrain - Automatic Transmission/Transaxle - 'AB60F Automatic Transmission/Transaxle: Automatic Thansmission System: Initialization"
A. Does the MIL "ON" reoccur with transmission performance DTCs resetting?
Most transmission performance DTCs are two4rip detection logic DTCs. For more information on two-trip detection, refer to TIS Techstream Help.
B. Does the transmission display any transmission shifting issues?
^ YES to A or B - Go to step 8.
^ NO to A and B - Continue test driving the vehicle and try to duplicate the MIL "ON" or abnormal transmission shifting. If unable to duplicate complaint after ECM (PCM) reprogramming, the repair is complete.
8. Replace the transmission assembly.
Refer to TIS, applicable model and model year Repair Manual:
9. Confirm the repair.
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