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Ground Circuits

MCU is grounded through pins No. 2, 14, 19 and 24. Pins No. 2, 14 and 24 are Brown wires. Pin No. 19 is Brown/Orange wire. Ground point is on right front shock tower. Ensure battery voltage exists between battery and pins No. 2, 14, 19 and 24. If voltage does not exist, check for open circuit. See WIRING DIAGRAMS article for more information.

MCU LOCATION

Application Location
325 Series & 735i Under Right Side of Dash
525i & 535i Behind Right Front Strut Tower