Engine Controls - MIL ON/DTC P0420 Set
ENGINEEG017-03
REVISED
Title:
M.I.L. "ON" DTC P0420
Models:
'01 Prius
November 14, 2003
TSB REVISION NOTICE:
^ March 2, 2007: The Applicable Warranty box in Warranty Information has been updated. The ECM part number of the Parts Information table has been updated, and a note has been added to the Parts Information table. The Required SSTs has been updated to the current format. Step 1 of the Repair procedure has been updated.
Previous versions of this TSB should be discarded.
Introduction
Some 2001 model year Prius vehicles may experience a M.I.L. "ON" with DTC P0420 due to an Electronic Control Module (ECM) (SAE term: Powertrain Control Module/PCM) software logic error. The ECM logic has been modified to prevent the M.I.L."ON" condition. Follow the repair procedures described below to improve this condition.
Applicable Vehicles
^ 2001 model year Prius vehicles produced BEFORE the Production Change Effective VIN shown below.
Production Change Information
Parts Information
Warranty Information
Applicable Warranty*:
The repair is covered under the Toyota Federal Emissions 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.
Required SSTs
Repair Procedure
1. Follow the P0420 DTC diagnosis. Refer to the Technical Information System (TIS) 2001 model year Prius Repair Manual: Diagnostics: Engine: Circuit Inspection (P0420).
2. If B1S2 readings indicate a defective catalytic converter, replace the catalytic converter.
3. Verify engine ECM (PCM). If ECM part number is 89661-47030, replace the engine ECM (PCM).
NOTE:
^ ECM (PCM) replacement applies to part number 89661-47030 ONLY.
^ Maintain steady throttle during cruise while performing Confirmation Driving Pattern found in the Repair Manual.
^ In some instances, both the catalytic converter and ECM (PCM) will need to be replaced.