BrakesModel years 2003–2003Manufacturer
Buzz at the accelerator pedal on the first acceleration after start (Supplemental Brake Assist self-test, normal)
The article names some 2003 Silverado, Suburban, Tahoe, Avalanche, Sierra, Yukon, Denali, Escalade and EXT vehicles; only vehicles with vacuum brake boosters.
FaultCrate・Buzz at the accelerator pedal on the first acceleration after start (Supplemental Brake Assist self-test, normal)
A buzz that can be heard and felt comes from the accelerator pedal area on the first acceleration after starting, only the first time the vehicle reaches approximately 10 mph (16 kph).
It does not occur again until the key is cycled off then on, and it may coincide with the 1-2 shift of the automatic transmission.
The noise is the Supplemental Brake Assist (SBA) performing a self-test; the SBA, mounted to the brake vacuum booster canister, is new for 2003 and supplies vacuum to the brake booster if vacuum is low or lost.
What to do
No technical document states a check or a repair.
Caution
- This is a normal condition and no repair should be attempted.
- The SBA is used only on vehicles with vacuum brake boosters, not on vehicles with Hydra-Boost brake systems.
Applies to
- The condition affects some 2003 Silverado, Suburban, Tahoe, Avalanche, Sierra, Yukon, Denali, Escalade and EXT vehicles.
See the evidence (1 documents, 6 passages)
| Document | Publisher | Date |
|---|---|---|
| [1]GM TechLink, March 2003 ↗ | ManufacturerGeneral Motors | 2003-03-01 |
Applies toThe condition affects some 2003 Silverado, Suburban, Tahoe, Avalanche, Sierra, Yukon, Denali, Escalade and EXT vehicles.
This condition affects some 2003 Silverado, Suburban, Tahoe, Avalanche, Sierra, Yukon, Denali, Escalade, and EXT vehicles.— [1]
First signsA buzz that can be heard and felt comes from the accelerator pedal area on the first acceleration after starting, only the first time the vehicle reaches approximately 10 mph (16 kph).
Owners may experience a buzz noise which can be heard and felt, from the accelerator pedal area on the first acceleration after starting the vehicle. It will occur only the first time the vehicle reaches approximately 10 mph (16 kph) after start-up.— [1]
First signsIt does not occur again until the key is cycled off then on, and it may coincide with the 1-2 shift of the automatic transmission.
It will not occur again until the key is cycled off then on. Based on the driving habits of the owner, the condition may occur at approximately the same time as the 1-2 shift of the automatic transmission.— [1]
Why it happensThe noise is the Supplemental Brake Assist (SBA) performing a self-test; the SBA, mounted to the brake vacuum booster canister, is new for 2003 and supplies vacuum to the brake booster if vacuum is low or lost.
This noise is caused by the Supplemental Brake Assist (SBA) performing a self-test. The SBA, which is mounted to the brake vacuum booster canister, is new for 2003 and provides vacuum for the brake booster in case of low vacuum or vacuum loss.— [1]
CautionThis is a normal condition and no repair should be attempted.
This is a normal condition and no repair attempts should be made.— [1]
CautionThe SBA is used only on vehicles with vacuum brake boosters, not on vehicles with Hydra-Boost brake systems.
The SBA is used only on vehicles equipped with vacuum brake boosters and is not used on vehicles equipped with Hydra-Boost brake systems.— [1]
Put together by FaultCrate from public records and technical documents. The cause and the repair are for the workshop to decide with the vehicle in front of it. Counts are records, not failure rates.
List the records (1 that can be opened)
Records whose recall number, document number or text matches. Each line says why it matched.
- Buzz at the accelerator pedal on the first acceleration after start: Supplemental Brake Assist self-test (normal)Manufacturer communication 2003-03-01・document number matches