Engine Controls - Rocking Sensation at 40 MPH
ENGINEEG020-06
REVISED
Title:
"ROCKING" FEELING AROUND 40 MPH
Models:
'06 RX 400h
October 18, 2006
TSIB REVISION NOTICE:
^ July 24, 2007: The T1 code in the Warranty Information table has been updated.
^ December 15, 2006: Part numbers for the HV ECU have been updated in the Parts Information table. The Calibration IDs in Figure 2 have been updated. The Note below Figure 2 has been updated.
Previous versions of this TSIB should be discarded.
Introduction
Under certain circumstances, 2006 model year RX 400h owners may experience a back and forth ~rocking" feeling while attempting to maintain the vehicle at a constant speed around 40 mph. The Hybrid Vehicle (HV) ECU logic has been updated to help improve this condition.
Applicable Vehicles
^ 2006 model year RX 400h vehicles produced BEFORE the Production Change Effective VINs shown below.
Production Change Information
Warranty Information
This repair is covered under the Lexus Hybrid Vehicle Component Warranty.
Applicable Warranty*:
This warranty is in effect for 96 months or 100,000 miles, whichever occurs first, from the vehicle's in-service date.
* Warranty application is limited to correction of a problem based upon a customer's specific complaint.
Parts Information
Required SSTs
Calibration ID Information
NOTE:
There are different calibration files for vehicles with, and without, transaxle oil coolers. In order to determine the configuration of your vehicle, shine a flashlight into the left front bumper cover vent. If the vehicle is equipped with a cooler, it will be easily visible.
Calibration Identification Chart
Repair Procedure
1. Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 1. Confirm if the HV ECU and ECM (PC M) calibrations have been updated. If the calibration IDs listed are NOT the latest calibrations go to step 2.
2. Connect the Diagnostic Tester to the vehicle and select CURRENT ECU CAL from the ECU REPROGRAM MAIN MENU. Determine the vehicle's current ECU calibrations (see Figure 2).
- The sample screen prints seen below are the 1 3.4a software version and may differ from subsequent software versions.
NOTE:
^ Anytime the HV ECU is reprogrammed, the engine ECM (PCM) MUST also be reprogrammed, even if the engine ECM (PCM) has the "New Calibration ID".
^ If ONLY the engine ECM (PCM) Calibration ID matches the "Current Calibration ID" shown in the Calibration Identification Chart in this TSIB, proceed with flash reprogramming.
^ If BOTH the engine ECM (PCM) and HV ECU Calibration IDs match the "New" calibration IDs shown in the Calibration Identification Chart, this vehicle has already been reprogrammed. Refer to the Technical Information System (TIS) for diagnostic procedures applicable to any stored DTCs.
3. If the ECU calibration ID is NOT the same as the New Calibration ID" listed previously, proceed to Flash Reprogram ECM (PCM).
4. Flash Reprogram HV ECU and ECM (PCM)
NOTE:
A battery charger MUST be connected to the battery and set at a medium charge setting during the Flash Reprogram procedure in order to maintain proper battery voltage and prevent damage to the HV ECU and ECM (PCM).
Follow the procedures outlined in TSIB No. S0001-01, "ECU Flash Reprogramming Process," and flash the ECM (PCM) with the new calibration file update.
NOTE:
If the "Check Engine" light is ON when the ignition is turned back on to begin the reprogramming process, a scan tool cable problem exists. Refer to TSIB No. SS003-01, "ECU Flash Reprogramming Error Message."
5. Start the engine and warm it up to normal operating temperature before test-driving.
6. Test-drive the vehicle to confirm proper vehicle operation (and proper laser cruise control operation, if so equipped).
7. Enter the required information on the Authorized Modifications Label and affix it to the vehicle at the location shown in Figure 1. The Authorized Modifications Label is available through the MDC, P/N 00451-00001-LBL.
8. Calibration update is complete.
^ Select premium unleaded gasoline with an Octane Rating of 91 or higher for optimum engine performance.
^ The effect of the new calibration may become more apparent after several days of driving as the ECM (PCM) "learned values" are re-established from the customer's driving.