Brakes - Slip Control ABS/ASC +T Operation/Description: Overview

Group 34
Brakes



Bulletin Number
34 01 92 (2129)



Woodcliff Lake, NJ
September 1992
Product Engineering



SUBJECT:
Slip Control (ABS/ASC+T) for M60 Equipped Vehicles

MODELS:
740i/iL (E32)

Situation:
With the introduction of the M60 engine, a change in ASC+T operating parameters becomes necessary. The previous interconnected driving management system of Engine Control (DME), Throttle Control (EML), Slip Control (ABS/ASC+T), and Transmission Control (EGS) is not possible with the 740i/iL due to the absence of an EML system.

The 740i/iL is therefore equipped with an Auxiliary Throttle Valve Control system (ADS II) to allow ASC/MSR regulation in the event of excessive wheel slip during acceleration or engine braking.

Note:





ABS functions, and most ASC+T functions are unchanged from previously introduced systems (ABS, ASC and ASC+T). Refer to T.R.I.'s 34 04 83 (2035), 12 01 89 (2095), and 34 01 90 (2105) if additional information is required. Only the changed operating parameters specific to ASC+T as installed on M60 equipped vehicles will be discussed in this bulletin.



The ASC+T system as installed on M60 equipped vehicles makes use of three new components which comprise the Auxiliary Throttle Valve Control system (ADS II):






A choke-valve plate assembly (auxiliary throttle valve) which is normally held open by spring pressure, mounted upstream of the throttle body;






- An ADS II actuator which closes the chokevalve plate by action of a bowden cable; and,


- An ADS II Control Module which controls the ADS II actuator.

The ADS II actuator is mounted forward of the left front wheel well, and the ADS II control module is mounted in the right-hand kick panel.