Some 2010-2012 HS 250h vehicles equipped with a 2AZ-FXE engine may exhibit a MIL ON condition with DTC P0136 (oxygen sensor circuit malfunction; Bank 1 Sensor 1).
The oxygen sensor and Hybrid Vehicle ECU (HV ECU) logic have been modified to reduce the possibility of this condition occurring.
Model Model year Previous cal. ID New cal. ID
HS 250h 2010-2011 37503000 37503200
2010-2011 37503100 37503200
2012 37508000 37508100
Model year Previous P/N Current P/N Part name
2010-2011 89981-75030 89981-75032 Computer, hybrid control
2010-2011 89981-75031 89981-75032 Computer, hybrid control
2012 89981-75090 same Computer, hybrid control
All 89465-75010 same Oxygen sensor
- 00451-00001-LBL same Authorized modification label
NOTE: The HV ECU 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 through Dealer Daily – Dealer Support Materials Orders.
TIS Techstream or Techstream Lite
P/N TSPKG1 or TSLITEDLR01
NOTE: Software version 7.10.030 or later is required.
GR8 Battery Diagnostic Station, P/N 00002-MCGR8
NOTE: The diagnostic tester is NOT recommended for flash reprogramming with this calibration file. Use TIS Techstream or an approved J2534 interface to perform this update. Visit techinfo.toyota.com for more information regarding J2534 reprogramming.
- Using TIS Techstream, check for stored DTCs. If only DTC P0136 is present, proceed to Step 2.
- Remove and replace the oxygen sensor (Bank 1 Sensor 1).
- Check for the Authorized Modifications Label affixed to the vehicle in the location shown in the accompanying photo. Confirm if the HV ECU calibration has been updated. If the calibration IS listed is NOT the latest HV ECU calibration, go to Step 4.
- Flash reprogram the HV ECU. The GR8 Battery Diagnostic Station MUST be used in the Power Supply Mode to maintain battery voltage at 13.5 volts while flash reprogramming. Follow the procedures outlines in Service Bulletin L-SB-0015-10 “Techstream ECU Flash Reprogramming Procedure, and flash the HV ECU with the NEW calibration file update.
- Place the vehicle into Ready “ON” mode and test drive to confirm proper vehicle operation of the HV ECU.
- Install the Authorized Modifications Label. Using a permanent marker, enter the following information on the label:
- HV ECU part number
- Calibration ID(s)
- Dealer Code
- Repair Date
- Change authority (L-SB-0035-12)
Affix the Authorized Modifications Label to the vehicle at the location shown in the photo.