Toyota Sienna Forum - banner

1 - 2 of 2 Posts

Premium Member
745 Posts
Discussion Starter #1
This is an interesting problem whose fix is not obvious. The symptom is a wet carpet in the third row seat storage well. Here is the start of the TSB.


Some 2011 – 2012 model year Sienna vehicles may exhibit a water leak condition in the 3rd row seat stow area. Water can be found in the rear stow well with no indication of water present in other areas of the cabin. Typically, this condition can be found while the vehicle is parked on an incline during a rain storm.

Applicable Warranty

• This repair is covered under the Toyota Basic 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 occurrence of the specified condition described in this bulletin.

Water Leak Inspection Procedure

1. Visually confirm water is present in the 3rd row seat stow area.

2. Water test vehicle while parked on an incline.

A. Raise the front of the vehicle to 17 degrees (front wheels approximately 24 inches off the ground). For example, this can be done by placing the front of the vehicle on an alignment rack.

B. Place a water hose on the windshield to simulate a rain storm.

C. While water is running, inspect the rear of the vehicle in the 3rd row seat stow area for evidence of water entering through the sheet metal panels.

NOTE: Water leak inspection may take up to 5 minutes before leak condition can occur.

D. If water leak is identified in the 3rd row seat stow area, proceed to the following repair procedures. If water leak condition has not been identified, STOP. This bulletin does not apply. Continue diagnosis using typical water leak procedures.
There are several potential leak sources: incompletely sealed body seams in the engine compartment, unibody access holes, and a brake line clip hole. One potential drain location is opened during the repair. The rear well leak sites are also sealed: several unsealed body seams and two inspection holes.

The key portion of this TSB is that the leak occurs when the vehicle gets wet pointing uphill while on an incline.
1 - 2 of 2 Posts