Hybrid System - MIL ON, DTC P1121 Set

T-SB-0231-12

November 29, 2012

MIL "ON" DTC P1121

Service Category
Engine/Hybrid System

Section
Cooling

Market
USA





Applicability

Introduction

Some customers with 2004 - 2007 model year Prius vehicles may experience a MIL "ON" condition with Diagnostic Trouble Code (DTC) P1121, Coolant Flow Control Valve Position Sensor Stuck. Use the repair procedure below to address this condition.

Production Change Information





This bulletin applies to vehicles produced BEFORE the Production Change Effective VINs shown.





Parts Information





Warranty Information





Required Tools & Equipment

Repair Procedure

1. Check DTCs and confirm P1121 is present.





2. Remove the engine under cover LH.





3. Drain the engine coolant.

Refer to the Technical Information System (TIS) applicable model and model year Repair Manual:

^ 2004 / 2005 Prius:
Engine/Hybrid System - Cooling - "Engine Coolant (1NZ-FXE): Replacement"

^ 2006 / 2007 Prius:
Engine/Hybrid System - Cooling - "1NZ-FXE Cooling: Coolant: On-vehicle Inspection"





4. Mark the upper coolant hose (hose to heater core). Take note of the original location of all coolant hoses.

5. Remove the electrical connector on the coolant flow control valve.

6. Remove all three coolant hoses on the coolant flow control valve.

7. Remove the coolant flow control valve from the vehicle body.

8. Install the replacement coolant flow control valve in reverse order of removal.

9. Install the engine under cover LH.

10. Refill engine coolant.

Refer to TIS applicable model and model year Repair Manual:

^ 2004 / 2005 Prius:
Engine/Hybrid System - Cooling - "Engine Coolant (1NZ-FXE): Replacement"

^ 2006 / 2007 Prius:
Engine/Hybrid System - Cooling - "1NZ-FXE Cooling: Coolant On-vehicle Inspection"

11. Clear DTCs.

© 2012 Lexus, a division of Toyota Motor Sales, USA