Radio - Whine On AM Band

GROUP 65
Cruise, Alarm, Monitors

65 03 00

Woodcliff Lake, NJ
Service Engineering

December 2000

SUBJECT:
E38/E39/E53 DSP Amplifier Induced Whine on AM Band

MODEL:
E39, E38 produced from 05/98 up to 07/00 with DSP E53 produced up to 07/00 with DSP

SITUATION:
DSP induced interference (constant "whine") may be heard when the radio is tuned to certain stations of the AM band (e.g. 880 KHz, or 1010 KHz).

CAUSE:
Excessive electromagnetic emissions from DSP amplifier.

CORRECTION:
On a customer complaint basis only, and after verifying the complaint, install an improved DSP amplifier P/N 65 12 6 905 119.

NOTE:
The part number has not been changed. The improved amplifier can be identified by the hardware and software versions: HW 03 / SW 04, printed on the label on the DSP.

PROCEDURE:
To verify the complaint and replace the DSP amplifier: (Perform the following procedure outside the shop/garage. Interference from indoor lighting and computers is strong enough to cover the amplifier "whine").

1. Start the engine; turn "ON" the radio and select AM band.

2. If the constant (not oscillating) "whining" noise can be heard on certain stations in the upper AM band range, then replace the DSP amplifier. For the replacement procedure refer to the BMW Technical Information System (TIS) Repair Manual RA 65 12 070.

3. Recode DSP amplifier using DIS/MoDiC 23.0 (or higher).

PARTS INFORMATION

Part Number Description Quantity

65 12 6 905 119 DSP amplifier 1





WARRANTY INFORMATION
Covered under the terms of the BMW New Vehicle Limited Warranty.