Engine Controls - MIL ON/DTC's P2237/P2238 Set
T-SB-0294-08September 11, 2008
M.I.L. "ON" DTC P2237 and/or P2238
Service Category
Engine/Hybrid System
Section
Engine Control
Market
USA
Applicability
Introduction
Some 2008 - 2009 model year Camry HV vehicles may exhibit a M.I.L. "ON" condition with one of the following Diagnostic Trouble Codes (DTCs):
^ P2238 - Oxygen (A/F) Sensor Pumping Current Circuit Low (Bank 1 Sensor 1)
^ P2237 - Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 1 Sensor 1) An improved engine wiring harness has been developed to address this condition. Use the following repair procedure to diagnose and repair customer complaint vehicles.
Production Change Information
This TSB applies to vehicles produced BEFORE the Production Change Effective VINs shown below.
Warranty Information
APPLICABLE WARRANTY
^ This repair is covered under the Toyota Comprehensive Warranty. This warranty is in effect for 36 months or 36,000 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 Tools & Equipment
Repair Procedure
1. Using TIS Techstream check for stored DTCs.
2. Verify DTC(s) P2238 and/or P2237 are present.
NOTE
If other A/F sensor DTCs are present along with any of the DTCs listed above this TSB does NOT apply. Follow Repair Manual procedure to diagnose those DTCs.
3. Follow Repair Manual procedure to inspect the A/F sensor heater and Engine Room Junction Block (A/F Relay).
Refer to the Technical Information System (TIS) applicable model year Camry HV Repair Manual:
2008 / 2009 Camry HV Engine/Hybrid System - Engine Control - "2AZ-FXE Engine Control System: SFI System: P2237: Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 1 Sensor 1)"
4. If the A/F sensor heater and Engine Room Junction Block (A/F Relay) are within Repair Manual specifications replace the engine wire harness.
NOTE
It is necessary to remove the intake manifold and inverter assembly to access the engine wire harness.
For inverter assembly removal:
2008 / 2009 Camry HV Engine/Hybrid System - Hybrid/Battery Control System - "P311 Hybrid Vehicle Control: Inverter with Converter: Removal"
For intake manifold removal:
2008 / 2009 Camry HV Engine/Hybrid System - Engine Mechanical - "2AZ-FXE Engine Mechanical: Engine Assembly: Removal"
For inverter assembly installation:
2008 / 2009 Camry HV Engine/Hybrid System - Hybrid/Battery Control System - "P311 Hybrid Vehicle Control: Inverter with Converter: Installation"
For intake manifold installation:
2008 / 2009 Camry HV Engine/Hybrid System - Engine Mechanical - "2AZ-FXE Engine Mechanical: Engine Assembly: Installation"
5. After engine wire harness replacement clear DTCs and verify that no DTCs reset. Then warm vehicle to operating temperature and test drive to verify repair.