Please see T-SB-0079-18 Revision1
Introduction:
Some 2010 model year Prius and Prius Plug-in Hybrid vehicles may exhibit a condition where the brake, ABS, and/or TRAC warning light(s) are on and/or a Check VSC message displays. Diagnostic Trouble Codes (DTCs) C1252, C1253, C1256, and C1391 may be stored. This condition may be caused by a small internal brake fluid leak inside the brake booster assembly with master cylinder. Follow the Repair Procedure in this bulletin to address this condition.
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.
***** This repair is now covered by Customer Support Program ZJB
Repair Procedure:
1. Confirm the condition exists.
Are the brake, ABS, and/or TRAC warning light(s) ON and/or does a Check VSC message display?
YES — Continue to step 2.
NO — This bulletin does NOT apply. Continue diagnosis using the applicable Repair Manual.
2. Using Techstream, check for stored DTCs. Record ANY stored DTCs. Are ANY of the following DTCs stored:, C1252, C1253, C1256, or C1391?
YES — Continue to step 3.
NO — This bulletin does NOT apply. Continue diagnosis using the applicable Repair Manual.
3. Replace the brake booster assembly with master cylinder and the brake booster pump assembly with NEW parts.
4. Using Techstream, confirm the calibration ID. Refer to the Calibration Information table on page 3.
5. Update the skid control Engine Control Unit (ECU) to the latest calibration ID. 6. Test-drive the vehicle to confirm the repair.
Introduction:
Some 2010 model year Prius and Prius Plug-in Hybrid vehicles may exhibit a condition where the brake, ABS, and/or TRAC warning light(s) are on and/or a Check VSC message displays. Diagnostic Trouble Codes (DTCs) C1252, C1253, C1256, and C1391 may be stored. This condition may be caused by a small internal brake fluid leak inside the brake booster assembly with master cylinder. Follow the Repair Procedure in this bulletin to address this condition.
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.
***** This repair is now covered by Customer Support Program ZJB
Repair Procedure:
1. Confirm the condition exists.
Are the brake, ABS, and/or TRAC warning light(s) ON and/or does a Check VSC message display?
YES — Continue to step 2.
NO — This bulletin does NOT apply. Continue diagnosis using the applicable Repair Manual.
2. Using Techstream, check for stored DTCs. Record ANY stored DTCs. Are ANY of the following DTCs stored:, C1252, C1253, C1256, or C1391?
YES — Continue to step 3.
NO — This bulletin does NOT apply. Continue diagnosis using the applicable Repair Manual.
3. Replace the brake booster assembly with master cylinder and the brake booster pump assembly with NEW parts.
4. Using Techstream, confirm the calibration ID. Refer to the Calibration Information table on page 3.
5. Update the skid control Engine Control Unit (ECU) to the latest calibration ID. 6. Test-drive the vehicle to confirm the repair.