MS5.1 Engine Control Module: The ECM is located in the under hood E box (below). The following modified controls / functions have been made to MS45.1 for use in the E60.

New hot film air mass sensor (HFM).
Changed data record variant (matched to E60).
Lead to the CAS for start enable (starting relay is integrated in the CAS). (automatic/SMG transmissions only).
The Driving Dynamics control (FDC) signal is transmitted via the PT-CAN.
The cruise control (FGR) signal is sent from the MFL via the PT-CAN to the ECM.
Connection of the intelligent battery sensor (IBS) to the bit-serial data interface (BSD).
The software for power management (vehicle electrical system) is integrated in the ECM.
The A/C compressor is activated via the PT-CAN.
Fault diagnosis is performed through the SGM via the PT-CAN to the ECM.
Activation of the ECM main relay (525i / 530i in E box, 545i in IVM).
Bosch LSU 4.2 linear lambda oxygen sensors (pre-catalyst as in N62).
Mini hot film air mass sensor (HFM) in the secondary air system.

Fig 1: Identifying ECM

Courtesy of BMW OF NORTH AMERICA, INC.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

New System Components / Functions

Use the Manual With the Right Hardware

When to See a Mechanic