Brakes - Clunk Noise Diagnosis, A.B.S. Self-Check

90nissan02 Section:
Classification:
BR90-001 Brakes

Reference:
TECHNICAL BULLETIN NTB90-015
Models:
1990 300ZX (Z32)
Date:
February 22, 1990
A.B.S. "SELF-CHECK"/FRONT BRAKE CLUNK NOISE DIAGNOSIS


SERVICE INFORMATION

In previously issued Technical Bulletin BR89-008/TS89-163, entitled "Front Brake Clunking Noise in Reverse", a countermeasure was described which would eliminate the "clunk" noise in reverse if it was caused by a very small amount of brake pad movement in the calipers.



However, when diagnosing this noise, it is important to distinguish between the brake "clunk" noise in reverse and the normal sound made by the Anti-lock Brake System (A.B.S.) "self-check" function. If a customer complains of a "clunking noise" during braking, use the following chart to analyze the noise.
Before applying the countermeasure described in Technical Bulletin BR89-008/TS89-163, be sure to check the incident vehicle against the chart above to make certain the sound in the vehicle is not the result of "normal" A.B.S. "self-check" function. Please make note of this bulletin in the Brake [BR] Section of your copy of the 1989 Technical Bulletin Book.