Restraints - SRS Lamp ON/DTC B1861 Set
L-SB-0167-08December 11, 2008
SRS Light "ON" - DTC B1861
Service Category
Vehicle Interior
Section
Supplemental Restraint Systems
Market
USA
Applicability
Introduction
Some 2006-2008 MY IS250/350 vehicles may exhibit a SRS Light "On" condition with DTC B1861. Use the following information to address this condition.
Warranty Information
APPLICABLE WARRANTY
^ This repair is covered under the Lexus Restraint System Warranty. This warranty is in effect for 72 months or 70,000 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.
Parts Information
NOTE
Please see the Parts Identification Method section of this TSIB to determine the correct wire harness part number.
Required Tools & Equipment
Diagnostic/Repair Procedure
1. Using Techstream, confirm that DTC B1861 is present or in history.
2. Disconnect negative battery terminal.
3. Disconnect Driver Side Knee Air Bag Squib.
NOTE
To access Driver Side Knee Air Bag Squib refer to the Technical Information System (TIS), applicable model and model year Repair Manual:
^ 2006 IS 250/350:
Vehicle Interior Supplemental Restraint System "Supplemental Restraint System: Driver Side Knee Airbag Assembly: Removal"
^ 2007 IS 250/350:
Vehicle Interior Supplemental Restraint System "Supplemental Restraint System: Driver Side Knee Airbag Assembly: Removal"
^ 2008 IS 250/350:
Vehicle Interior Supplemental Restraint System "Supplemental Restraint System: Driver Side Knee Airbag Assembly: Removal"
Do NOT remove knee air bag.
4. Connect Driver Side Knee Air Bag Squib.
5. Connect negative battery terminal.
6. Turn engine switch (IG) on and wait at least 60 seconds.
7. Clear the DTCs stored in memory.
8. Turn engine switch (IG) off.
9. Turn engine switch (IG) on and wait at least 60 seconds.
10. Check for SRS DTC's.
A. If DTC B1861 is present, please refer to the TIS, applicable model and model year Repair Manual:
^ 2006 IS 250/350:
Vehicle Interior Supplemental Restraint System "Supplemental Restraint System: Airbag System: B1860/64: Short in Driver Side Knee Airbag Squib Circuit" (Reference DTC B1861: Open in Driver Side Knee Airbag Squib Circuit)
^ 2007 IS 250/350:
Vehicle Interior Supplemental Restraint System "Supplemental Restraint System: Airbag System: B1860/64: Short in Driver Side Knee Airbag Squib Circuit" (Reference DTC B1861: Open in Driver Side Knee Airbag Squib Circuit)
^ 2008 IS 250/350:
Vehicle Interior Supplemental Restraint System "Supplemental Restraint System: Airbag System: B1860/64: Short in Driver Side Knee Airbag Squib Circuit" (Reference DTC B1861: Open in Driver Side Knee Airbag Squib Circuit)
B. If DTC B1861 is no longer present, replace the Instrument Panel Wire Harness.
Instrument Panel Wire harness Part Number Identification Method
1. The part number to order the correct part is located on the harness near the connector for the right knee airbag assembly. To access the part tag, remove right side knee airbag assembly. Refer to Technical Information System (TIS), applicable model and model year Repair Manual:
^ 2006/2007/2008 IS 250/350:Vehicle Interior Supplemental Restraint System "Supplemental Restraint System: Front Passenger Side Knee Airbag Assembly: Removal"
Instrument Panel Header Wire Harness Replacement
1. Remove Rear Console Box.
To remove the Rear Console Box refer to the Technical Information System (TIS), applicable model and model year Repair Manual:
^ 2006/2007/2008 IS 250/350:Vehicle Interior Interior Panels/Trim "Rear Console Box: Removal"
2. Remove Instrument Panel Safety Pad.
To remove the Instrument Panel Safety Pad refer to the Technical Information System (TIS), applicable model and model year Repair Manual:
^ 2006/2007/2008 IS 250/350:Vehicle Interior Interior Panels/Trim "Instrument Panel Safety Pad: Removal"
3. Replace Instrument Panel Wire Harness.
Unplug the harness from each connector on the vehicle. Make note of harness routing.
4. Install the new Instrument Panel Wire Harness.
Route and plug in the new harness ensuring the connectors are fully installed into the mating connector.
5. Reinstall the Instrument Panel Safety Pad.
To reinstall the Instrument Panel Safety Pad refer to the Technical Information System (TIS), applicable model and model year Repair Manual:
^ 2006/2007/2008 IS 250/350: Vehicle Interior Interior Panels/Trim "Rear Console Box: Installation"
6. Reinstall the Rear Console Box.
To reinstall the Rear Console Box refer to the Technical Information System (TIS), applicable model and model year Repair Manual:
^ 2006/2007/2008 IS 250/350: Vehicle Interior Interior Panels/Trim "Rear Console Box: Installation"