Restraints - SRS Lamp On/DTC's B1821/B1826 Set
T-SB-0042-11May 23, 2011
SRS Light "ON" DTC B1821/B1826 Open Front Side Squib Circuit
Service Category
Vehicle Interior
Section
Supplemental Restraint Systems
Market
USA
Applicability
Introduction
Some 2004 - 2009 model year Prius vehicles may exhibit an SRS light "ON" condition with Diagnostic Trouble Code (DTC) B1821 and/or B1826. An updated wire harness is available to address this condition. Follow the procedures in this bulletin to replace the floor wire harness.
Production Change Information
This TSB applies to vehicles produced BEFORE the Production Change Effective VINs shown.
Warranty Information
Parts Information
Required Tools & Equipment
TSB Overview
After confirming the vehicle condition matches this bulletin this TSB will direct you to replace the floor wire harness. In order to do this it is necessary to first remove several major components such as the instrument panel front seats headliner and seat belts. This bulletin provides detailed instructions on the removal and installation of these components.
Inspection Procedure
1. Inspect the floor wire harness and the center airbag sensor assembly following the diagnostic procedure in the Repair Manual.
Refer to the Technical Information System (TIS) applicable model year Prius Repair Manual:
DTC B1821:
^ 2004 / 2005 Prius:
Vehicle Interior - Supplemental Restraint Systems - "Supplemental Restraint System: B1821/55 Open in Side Squib"
^ 2006 / 2007 / 2008 / 2009 Prius:
Vehicle Interior - Supplemental Restraint Systems - "Supplemental Restraint System: Airbag System: B1820/55-B1823/55: Shod in Front Driver Side - Side Squib Circuit"
DTC B1826:
^ 2004 / 2005 Prius:
Vehicle Interior - Supplemental Restraint Systems - "Supplemental Restraint System: B1826/56 Open in Side Squib"
^ 2006 / 2007 / 2008 / 2009 Prius:
Vehicle Interior - Supplemental Restraint Systems - "Supplemental Restraint System: Airbag System: B1825/560-B1828/56: Short in Front Passenger Side - Side Squib Circuit"
2. If NO concern is identified after inspecting the floor wire harness and the center airbag sensor assembly follow the Repair Procedure below to replace the corresponding floor wire harness.
Repair Removal
1. Disconnect the cable from the negative (-) battery terminal. (B, L, R)
CAUTION
2. Remove the service plug. (B, L)
Refer to the Technical Information System (TIS) applicable model year Prius Repair Manual:
3. Remove the No. 1 instrument panel register assembly. (B, L, R)
Detach the 2 claws and 4 clips and remove the instrument panel register.
4. Remove the lower instrument panel finish panel sub-assembly. (B, L, R)
A. Remove the 2 screws.
B. Disconnect the hood lock control cable.
C. Detach the 4 claws and 5 clips.
D. Disconnect all connectors and remove the instrument panel finish panel.
5. Remove the upper instrument panel finish panel sub-assembly. (B, L, R)
A. Detach the 3 claws and 4 clips.
B. Disconnect the connector and remove the instrument panel finish panel.
6. Remove the No.3 instrument panel register assembly. (B, L, R)
A. Detach the claw and 5 clips.
B. Disconnect the connector and remove the instrument panel register.
7. Detach the 6 clips and remove the No. 4 instrument panel register assembly. (B, L, R)
8. Remove the No.2 instrument panel register assembly. (B, L, R)
Detach the 2 claws and 4 clips and remove the instrument panel register.
9. Remove the instrument cluster finish panel assembly center. (B, L, R)
A. Remove the 2 screws.
B. Detach the 4 clips and remove the instrument cluster finish panel.
10. Remove the instrument cluster finish panel assembly center. (B, L, R)
A. Using a clip remover remove the clip from the instrument panel finish panel lower center.
B. Detach the 4 claws and 2 clips and remove the instrument panel finish panel.
11. Remove the No.1 instrument panel under cover sub-assembly by detaching the 2 claws.(B, L, R)
12. Remove the glove compartment door stopper sub-assembly. (B, L, R)
Holding the part indicated in the illustration remove the glove compartment door stopper from the glove compartment door.
13. Remove the glove compartment door assembly. (B, L, R)
A. While pushing in the sides of the glove compartment door as indicated by the arrows open the door to release it from the 2 stoppers.
B. Open the door until it is horizontal.
C. Pull the glove compartment door toward the rear of the vehicle to detach the 2 hinges and remove the glove compartment door.
14. Remove the Body ECU. (B, L)
A. Remove the 2 bolts for the protective plate.
B. Remove the 3 bolts for the Body ECU.
15. Remove the left and right front seat. (B, L, R)
2004 - 2005 MY:
A. Using a plastic pry tool (or equivalent) disengage the 3 claws and remove the seat track outer cover LH.
B. Using a plastic pry tool (or equivalent) disengage the 2 claws and remove the seat track bracket cover inner LH.
C. Remove the front seat headrest assembly.
D. Remove the front seat assembly.
(1) Lift up the seat track adjusting handle and move the seat to the rearmost position.
(2) Remove the 2 bolts on the front side of the seat.
(3) Lift up the seat track adjusting handle and move the seat to the foremost position.
(4) Remove the 2 bolts on the rear side of the seat.
(5) Disconnect the connectors under the seat. Then remove the front seat.
2006 - 2009 MY:
Refer to TIS applicable model year Prius Repair Manual:
^ 2006 / 2007 / 2008 / 2009 Prius:
Vehicle Interior - Seat - "Seat Front Seat Assembly: Removal"
16. Remove the instrument panel rear console box. (B, L, R)
Refer to TIS applicable model year Prius Repair Manual:
^ 2004 / 2005 Prius:
Vehicle Interior - Interior Panels/Trim - "Console Box Sub-Assy Rear: Replacement"
^ 2006 / 2007 / 2008 / 2009 Prius:
Vehicle Interior - Interior Panels/Trim - "1nstrument Panel: Rear Console Box: Removal"
17. Remove the rear console box mounting bracket by removing the 4 bolts. (B, L, R)
18. Remove the rear seat cushion assembly. (B, L, R)
Pull up the 2 front portions of the seat cushion then remove it.
19. Remove the floor panel left side. (B, L, R)
A. Remove the 3 bolts and 1 clip.
B. Remove the bracket.
20. Remove the floor panel right side. (B, R)
A. Remove the 3 bolts and 1 clip.
B. Remove the bracket.
21. Remove the rear seatback assembly LH. (B, L)
A. Open the front part of the rear floor deck board No. 1.
B. Fully fold the seatback forward.
C. Remove the 2 bolts and seatback.
22. Remove the battery bracket reinforcement by removing the 7 bolts. (B, L)
23. Remove the No. 6 battery carrier panel by removing the 3 bolts and 2 nuts. (B, L)
24. Remove the headliner. (B, L, R)
Refer to TIS applicable model year Prius Repair Manual:
^ 2004 / 2005 Prius:
Vehicle Interior - Interior Panels/Trim - 'Roof Headlining Assy: Replacement"
^ 2006 / 2007 / 2008 / 2009 Prius:
Vehicle Interior - Interior Panels/Trim - "Interior: Roof Headlining: Removal"
25. Remove the carpet. (B, L, R)
A. Remove the audio amplifier (if equipped).
B. Remove the NAV ECU (if equipped).
C. Remove the 4 clips located under the rear seat cushion area.
D. Remove the carpet.
26. Remove the No.3 air duct rear. (B, L, R)
A. Detach the 10 claws and then remove the No.3 air duct rear.
B. Detach the clip and remove the right floor duct going to the rear.
C. Detach the clip and remove the left floor duct going to the rear.
27. Remove the quarter vent duct. (B, R)
A. Disconnect the connector.
B. Remove the clamp then disconnect the wire harness.
C. Remove the bolt clip and the quarter vent duct.
28. Remove the 3 clips and the ventilator duct inner.
(B, R)
29. Remove the battery blower. (B, R)
A. Remove the 3 nuts then disconnect the battery blower assembly from the vehicle.
B. Remove the connector clamp and battery blower.
30. Remove the floor harness. (B, L, R)
Note mounting and routing locations.
^ For the left harness to be removed the rear mount for the Curtain Side Airbag (CSAB) must be removed.
NOTICE
Do NOT allow the CSAB to hang unsupported as it could be damaged.
NOTE
For vehicles equipped with auto leveling headlights, the left harness is connected to the rear leveling sensor mounted under the vehicle (see Figure 24).
^ For the right harness the battery fan relay will need to be installed onto the new harness.
Repair Procedure: Installation
NOTE
^ Installation is in the reverse order of removal. Only key points are mentioned below.
^ Prior to reinstalling the headliner, ensure that the roof harness and CSAB connectors are fully seated.
1. Install the new harness.
Install the new harness and ensure that it is routed correctly and all the connectors are fully seated.
Right Harness Only: Install the HV battery fan relay into the new harness.
2. Reinstall the left rear seatback with the 2 bolts.
Torque: 36.8 N*m (375 kgf*cm, 27 ft*lbf)
3. Reinstall the front seats.
Torque: 37 N*m (377 kgf*cm, 27 ft*lbf)
2006 - 2009 MY RH seat ONLY: Initialize the Occupant Classification System.
Refer to TIS applicable model year Prius Repair Manual:
2006 / 2007 / 2008 / 2009 Prius:
Vehicle Interior- Supplemental Restraint Systems - "Supplemental Restraint System: Occupant Classification System: Initialization"
4. Clear DTCs. Cycle the ignition and confirm DTCs do NOT reoccur.
5. Initialize power systems (windows moonroof etc.). Refer to appropriate service bulletin.