EG047-05
October 19, 2005
Title:
M.I.L. “ON” DTC P0420
Models:
’01 – ’03 Sienna
Introduction
Under certain driving conditions, some 2001 – 2003 model year Sienna vehicles may exhibit a M.I.L. “ON” with the following DTC:
- P0420 (Catalyst System Efficiency Below Threshold [Bank 1])
The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has been modified to improve this condition.
Applicable Vehicles
- 2001 – 2003 model year Sienna vehicles.
Parts Information
| PREVIOUS PART NUMBER | CURRENT PART NUMBER | PART NAME | QTY |
|---|---|---|---|
| 89661-08061 | 89661-08062 | Module, Engine Control | 1 |
| 89661-08070 | 89661-08071 | ||
| 89661-08080 | 89661-08081 |
Warranty Information
| OP CODE | DESCRIPTION | TIME | OFP | T1 | T2 |
|---|---|---|---|---|---|
| 895011 | R & R Engine Control Module | 0.5 | 89661-08061
89661-08070 89661-08080 | 8A | 71 |
Applicable Warranty*:
This 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
| ITEM NO. | SPECIAL SERVICE TOOLS (SSTs) | PART NUMBER | QTY | DRW** |
|---|---|---|---|---|
| 1 | Toyota Diagnostic Tester Kit*
NOTE:
| TOY220036 | 1 | 9 |
* Essential SSTs.
** Refers to drawer number in SST Storage System.
NOTE:
Additional Diagnostic Tester Kits, Program Cards, or other SSTs may be ordered by calling SPX/OTC at 1-800-933-8335.
- Verify DTC P0420 with the Diagnostic Tester by referring to the Technical Information System (TIS), 2001 – 2003 model year Sienna Repair Manual: Diagnostics: Engine: Pre-Check.
- Replace ECM (PCM). Follow the Repair Manual ECM replacement instructions.
Refer to TIS, 2001 – 2003 model year Sienna Repair Manual: Introduction: How To Troubleshoot ECU Controlled Systems: How To Use The Diagnostic Chart And Inspection Procedure.
- Perform the following steps to confirm that the vehicle is repaired.
A. Reset the Readiness test by using the “Clear DTC” function on the Diagnostic Tester.
- To clear the DTC, refer to TIS, 2001 – 2003 model year Sienna Repair Manual: Diagnostics: Engine: Pre-Check.
B. Perform Readiness Monitor Drive Patterns for Catalyst Monitor O2S type and
AF Sensor type. Refer to TSB No. EG003-02, “Readiness Monitor Drive Patterns,” procedures: Catalyst Monitor (O2S Type) and Catalyst Monitor (AF Sensor Type).
C. If a DTC is set during the above drive patterns, refer to the Diagnostic Trouble Code Chart in TIS, 2001 – 2003 model year Sienna Repair Manual: Diagnostics: Engine: Diagnostic Trouble Code Chart. Test drive the vehicle to confirm normal operation.
- If NO DTCs (pending or current) are stored, the repair is complete.
- 🚗【2026 MaxiCOM MK908 Pro II】Updated of the old ver. MK908P, MS908S Pro, Autel released the 2.0 version MK908 Pro II (No-IP limited ver. of MaxiSYS MS908S PRO II & MSultra) to bring you a brand-new experience at the same cost. 1) Hardware upgrade: Qualcomm 660, 4+128GB, the latest Android 10, etc.2) Advanced features: J2534 Pr0g.ramming, c.0ding, active test, 10+ newly added features. 3) Broader coverage: 150+ brands, FCA AutoAuth. One device can totally support all the needs of a repair shop.
- 🚗【J2534 Pr0gramming & C0ding】Take your vehicle diagnostics to professional heights with the MK908P II Pro’s J2534 RePr0gramming feature. Elite II Pro diagnostic scanner delivers OE-level precision for Pr0gramming and C0ding, making it a must-have for shops and advanced users. The MK908P II offers the same capabilities as high-end scanners like Elite II Pro, MS909, MS919, Ultra Lite, and Ultra S2, while delivering better overall value.
- 🚗【40 Service for 150+ brands】Same as the OE scanners like snap-on, maxisys ultra ms919 scanners, Autel MK908P II has strong service capability and can go deep into every part to perform matching and resetting functions. What is better than the OE tools is that 40 services are not just for one specific brand, but for over 150 makes, covering 99% of the models from 1996-2026. MK908P 2 also supports AutoAuth, and Re*nault SGW, so you don't have to worry about compatibility issues.
- 🚗【All System Diagnosis & Comprehensive Report】Code reader MK908PRO II, same as elite ii pro, is a professional automotive diagnostic tool compatible with all systems diagnostics. It can diagnose all symptoms of faulty parts, including reading and clearing DTC. View a live data stream from every system. That real-time data means no delay in getting to work. Pre and post-scan reports keep your clients informed of the repair details and provide them with the evidence to settle insurance claims.
- 🚗【Active Test Gives In-depth Knowledge of Cars】Unlike conventional mechanic scanners, escaner automotriz professional MS908S PRO II MK908P II allows users can get access to the vehicle subsystem and output commands to the related systems, thus driving the actuat0rs to perform a specific function and determining the integrity of the system or parts. Monitor the operation of the actuat0rs for accurate diagnostics, such as switching a solenoid, relay, or switch, between two operating states.
Last update on 2026-06-16 / Affiliate links / Images from Amazon Product Advertising API
- Great Present Idea: LAUNCH Scanner X431 Pro3 (V+) V5.0 is a top present choice for your father, husband, brother or boyfriend if they own a repair shop, or they are an auto technician. We provide 2 years no-fee update. This is a 2026 NEW Elite 5.0 Version high-end professional diagnostic scanner.
- [OE-Level ECU Coding] Say goodbye to complicated car fixes! With LAUNCH X431 PRO3 (V+) V5.0, tweak your car’s brain like a pro, no fancy ECU Coding skills needed! 1) Online/Offline operation of your choice; 2) Backup/restore coding data; 3) Detailed coding guidance. 4) Extensive database for 200+ brands (compatible with V.A.G, BMW, Ford, GM, etc.) >> Fix ECU issues fast, open secret settings for upgrades, replace parts hassle-free, or even make a personalized ride (e.g. seatbelt warning off, headlights flash when alarm, dashboard brightness change, moving pointer self-check). Enjoy 2 years of free updates to stay compatible and lifetime tech support to overcome any obstacle.
- [Topology Mapping + All Systems Scan] After connecting to the vehicle, you can enter the “Topology Mapping” to perform a deep scan of all on-board systems like CEM, ECM, TCM, ABS/BCM, DIM, ASDM, BBS, IMS, SWM, HUD, SCL, TACM, AUD, etc., to quickly understand interconnections and data flow between ECUs. LAUNCH PRO3 (V+) V5.0 professional escaner automotriz features intuitive color-coded topology showing all structures between vehicle modules, and coupled with 8000+ DTCs and step-by-step guidance to help you cut 70% diagnostic time. See results at a glance, simply click to check faults!
- [Experience Advanced Bi-directional Control in LAUNCH Scanner X431 PRO3 (V+) V5.0 60 seconds fault detection! This bidirectional scan tool will use 4000+ Active Tests to transform complex issues into simple and clear result. Just pick the test you need and follow the on-screen instructions. This LAUNCH scanner will automatically send commands to the ECU, get the actuators working, and show you the results. >> It covers all system-related actuators, be it “fans, lights, horn, doors, windows, brakes, throttle, A/C, clutches, mirrors, cameras, pumps, valves”, or anything else. And it’s all very straightforward, so even if you’re new to this, you’ll have no trouble getting the job done.
- [55+ Hot Reset Services] LAUNCH X431 PRO3 (V+) V5.0 car scanner empowers technicians with 55+ reset services, saving significant time and cost while ensuring vehicle systems operate at peak specification. It can calibrate complex systems like Steering Angle Sensor (SAS), Electronic Parking Brake (EPB), Battery Management System (BMS), and throttle adaptations. Perform oil resets, sunroof initializations, and injector coding, ensuring accurate system relearns and enhanced repair reliability for modern vehicles. Maximize workshop productivity and first-time fix rates.
Last update on 2026-06-17 / Affiliate links / Images from Amazon Product Advertising API
No products found.
This product presentation was made with AAWP plugin.