Water Pump Leak Inspection And Diagnostic Tips (T-SB-0103-20 REV1)

WATER PUMP LEAK INSPECTION AND DIAGNOSTIC TIPS

TECHNICAL SERVICE BULLETIN

APPLICABILITY

YEAR(S)	MODEL(S)	ADDITIONAL INFORMATION
2008 - 2024	4Runner, Camry, Corolla, Highlander, Highlander HV, Hilux, RAV4, Tacoma, Tundra
2013 - 2022	Avalon HV
2008 - 2022	Avalon, Sequoia
2018 - 2022	C-HR
2008 - 2025	Camry HV, Hiace
2023 - 2024	Corolla Cross HV, Sequoia HV, Sienna HV MaaS Package
2022 - 2024	Corolla Cross, Tundra HV
2020 - 2024	Corolla HV
2019 - 2025	Corolla Hatchback
2023 - 2025	Crown
2024	Grand Highlander, Grand Highlander HV, Tacoma HV
2008 - 2011, 2013-2021, 2024	Land Cruiser
2016 - 2024	RAV4 HV
2021 - 2024	RAV4 Prime, Sienna HV, Venza HV
2008 - 2020	Sienna
2009 - 2016	Venza

REVISION NOTICE 

June 19, 2024 Rev1: 

• Applicability has been updated to include some 2008 - 2025 model year Toyota vehicles. 
• The Introduction, Warranty Information, Procedures, and Diagnostic Procedure and Water Pump Replacement sections have been updated. 

Any previous printed versions of this bulletin should be discarded. 

INTRODUCTION

This Service Bulletin provides updated non-electric water pump leak inspection and diagnostic tips for some 2008 - 2025 model year Toyota vehicles.

WARRANTY INFORMATION

OP CODE	DESCRIPTION	TIME	OFP	T1	T2
N/A	Not Applicable to Warranty	-	-	-	-

APPLICABLE WARRANTY

• Warranty coverage is based on the failed component. Please refer to the Warranty Policy and Procedures Manual and the Powertrain Parts List for specific coverage. 
• Warranty application is limited to occurrence of the specified condition described in this bulletin. 

Warranty and Claim Submission: Warranty Policy 4.21 

• ANY leak repair to be performed under warranty requires photo documentation of the active leak. 
• This documentation showing the cause of the defect MUST be created prior to the start of the repair and attached to the warranty claim. 
• Photos MUST be clear and provide perspective image(s) that identify the vehicle identification number (VIN) and the affected component(s), and close-up image(s) that illustrate the defect or condition. 
• For additional information regarding application and eligibility, please reference Warranty Policy 4.21. 

WATER PUMP CONSTRUCTION

TEMPORARY AND ACTIVE LEAKS

Water pump replacement is NOT necessary for a temporary leak condition. The water pump should be replaced for an active leak condition. Examples of both conditions are shown below:

• As the water pump assembly rotates, a small amount of engine coolant is discharged to cool and lubricate the sliding surface of the mechanical seal and evaporates.
• If debris becomes lodged between the mating ring and seal ring, a small gap is formed. This allows coolant to bypass the mechanical seal, flow into the fluid catch pocket, and drain out of the weep hole. This condition is temporary and will no longer be present once the debris breaks up or works its way out of the seal.

DIAGNOSTIC PROCEDURE AND WATER PUMP REPLACEMENT

1. Confirm if there are leaks from other areas of the cooling system not including from the water pump assembly.
   NOTE: Refer to the applicable model and model year Repair Manual at TIS - Cooling System - On-Vehicle Inspection - Inspect for Coolant Leak. 

   Are ANY leaks present in the cooling system other than from the water pump?

   • YES -  Continue leak diagnosis using the applicable model and model year

     Repair Manual and correct any other cooling system leaks BEFORE proceeding.

   • NO -  Continue to step 2.
2. Is the coolant level below the "low" indicator on the reservoir and does the water pump appear to be actively leaking?
   • YES -  Replace the water pump. Refer to the applicable model and model year Repair Manual.
   • NO -  Continue to step 3.
3. Does the water pump pulley/bearing have excessive free play or does NOT turn smoothly?
   • YES -  Replace the water pump. Refer to the applicable model and model year Repair Manual.
   • NO -  Continue to step 4.
4. A paper towel should be used to determine if a leak is current or was temporary due to debris that has now cleared. Apply a dry paper towel to the coolant deposits around the water pump. If the paper towel remains dry, then the leak was temporary and the water pump does NOT need to be replaced. If the paper towel becomes wet with coolant, the leak is active and the water pump should be replaced.

   Is the paper towel wet with coolant?

   • YES -  Replace the water pump. Refer to the applicable model and model year Repair Manual.
   • NO -  No active leak is present. Confirm the coolant level in the reservoir is correct, adjust as necessary, and return the vehicle to the customer.
   NOTE: Thoroughly clean ANY coolant residue from the engine and surrounding areas.