Engine Controls - MIL ON/DTC's P2238/P0031
ENGINEEG034-04
REVISED
Title:
M.I.L. "ON" DTC P0031 AND/OR P02238
Models:
'04 Camry (2AZ-FE)
August 23, 2004
TSB REVISION NOTICE:
^ April 27, 2007: Applicable Warranty has been changed from "Toyota Specified Major Emission Control Component Warranty" to "Toyota Federal Emission Warranty". A calibration ID has been added to the Current Calibration IDs for A/T PZEV (CA) models in the Calibration Information table.
^ April 29, 2005: Parts Information has been updated to include Air Fuel Ratio Sensor for non-PZEV models, and the Flash Reprogram Procedure has been updated to include instructions for removal of the 10A ECU-IG fuse.
Previous versions of this TSB should be discarded.
Introduction
Under certain driving conditions, some 2004 model year Camry vehicles with 2AZ-FE engines may exhibit a M.I.L. "ON" condition with one or both of the following DTCs:
^ P0031 Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 1 Sensor 1)
^ P2238 Oxygen Sensor Pumping Current Circuit Low (For A/F Sensor) (Bank 1 Sensor 1)
The A/F sensor manufacturing process and the Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic have been modified to improve these conditions.
CAUTION:
Version 12.01a or later Diagnostic Tester software is required.
Applicable Vehicles
^ All 2004 model year Camry vehicles.
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 correction of a problem based upon a customer's specific complaint.
Parts Information
Required SSTs
Calibration Information
Repair Procedure
For DTC P0031 and/or P2238:
1. Replace Bank 1 Sensor 1 A/F Sensor.
2. Perform ECM (PCM) recalibration (see Calibration Procedure) with the NEW Calibration ID as shown above in the Calibration Information table.
Calibration Procedure
Verify Vehicle Condition
1. Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 1. Confirm if ECM (PCM) calibration has been updated. If NOT the latest ECM (PCM) calibration go to step 2.
2. Connect the Diagnostic Tester to the vehicle's DLC3 connector and select CURRENT ECU CAL from the ECU REPROGRAM MAIN MENU. Determine the vehicle's current ECU calibration (see Figure 2).
3. If ECU calibration ID is not the same as the "New Calibration ID" listed previously, proceed to Flash Reprogram ECM (PCM).
Flash Reprogram Procedure
Flash Reprogram ECM (PCM)
1. Remove the 10A ECU-IG fuse from the Instrument Panel Junction Block assembly. This action prevents possible activation of the ABS relay, resulting in ECM Reprogramming failure.
NOTE:
ECU damage may occur if 1OA fuse is NOT removed.
2. Follow the procedures outlined in TSB No. SS002-01, "ECU Flash Reprogramming Process," and flash the ECM (PCM) with the NEW calibration file update.
3. Reinstall the 10A ECU-IG fuse in the Instrument Panel Junction Block assembly.
4. 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.
5. Calibration update is complete.