WenmarOpen by Wenmar Pro

Service bulletin 521

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10009808
Published by NHTSA2004-10-25
Manufacturer's number521
Manufacturer's date2004-09-24
NHTSA componentSERVICE BRAKES, HYDRAULIC

NHTSA's summary

NOISES AND SQUEAKING AT THE REAR AXLE WHEN BRAKING - BRAKE PAD MAKES CONTACT WITH SUPPORT PLATE. QUALITY IMPROVEMENT WORKSHOP CAMPAIGN. *TT

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Brakes

Vehicles listed
PORSCHE CAYENNE S2003, 2004 (the catalog's model; the bulletin names a series or trim of it)
PORSCHE CAYENNE TURBO2003, 2004 (the catalog's model; the bulletin names a series or trim of it)

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
No. D7522026-02-05. Service bulletin. Parts information for parts withdrawal involving the caliper without brake pads. The part numbers affected are in the attached PDF. The vehicles associated are cars that use the part numbers in the PDF.
No. D7492025-12-05. Service bulletin. Parts information for parts withdrawal involving the brake disc 9Y0615301AJ
D7192025-06-02. Service bulletin. Parts information for Parts Withdrawal - 1 Set of Brake Pads for Disk Brake. Vehicles included are all cars that use part number 992698451R
No. D6892024-08-06. Service bulletin. Parts information for parts withdrawal involving the brake hose 9J1611707F and 9J1611708F
No. D6842024-07-02. Service bulletin. Parts information for parts withdrawal involving the retainer for brake hose/brake line
No. D6812024-06-05. Service bulletin. Parts information for parts withdrawal involving the retainer for brake hose/pressure difference sender. (9J1611845C, 9J1611846C, PAB906051C)
No. 1801.42022-04-05. Service bulletin. Advanced technical information for a brake squeal.
ATIALL416052021-06-28. Service bulletin. Understanding and addressing brake squeal complaints.
122-S6Q2R-062021-03-06. Service bulletin. Resubmitting at request of Mr. Bernard Hardgrave. Advanced technical information on brake fluid for all Porsche vehicles.
ATI-09032010-06-26. Service bulletin. PORSCHE: BRAKE BOOSTER DISTANCE SENSOR. VEHICLE HAS THE WARNING PHC UNAVAILABLE. THE VEHICLE HAS FAULT CODE 1673 FOR THE BRAKE BOOSTER DISTANCE SENSOR. THE SENSORS REPLACED HAVE BEEN FOUND NOT TO HAVE AN INTERNAL FAILURE. DISCONNECT THE ELECTRICAL CONNECTOR AND CLEAN THE CONTACTS. *PE