System Components

MS42/MS43 Engine Control Module:  The Engine Control Module (ECM) features a single printed circuit board with two 32-bit microprocessors.

The task of the first processor is to control:

• Engine Load 
• Electronic Throttle 
• Idle Actuator 
• Ignition 
• Knock Control 

Fig 1: Identifying Engine Control Module

The task of the second processor is to control:

• Air/Fuel Mixture 
• Emission Control 
• Misfire Detection 
• Evaporative Leak Detection 

Fig 2: Identifying ECM Connector Terminals

The 134 pin ECM is manufactured by Siemens to BMW specifications. The ECM is the SKE (standard shell construction) housing and uses 5 modular connectors. For testing, use the Universal Adapter Set (break-out box) Special Tool # 90 88 6 121 300.

Fig 3: Identifying System Components: Inputs - Processing - Outputs (1 Of 2)

Fig 4: Identifying System Components: Inputs - Processing - Outputs (2 Of 2)