Pin Arrangement: 1992 and later 325i, M3
Pin # For
1 Not used
2 Not used
3 Not used
4 A/C compressor control
5 Normal speed relay
6 Climate control module
7 Starter immobilization relay
8 Not used
9 For Euro 3.0 M3 to oil temp gauge. Not used in US M50s
10 Reversing light switch
11 Engine temperature
12 Engine coolant temperature
13 Oxygen sensor, fuel pump relay
14 On Inst.cluster on rear of speedo, vehicle speed output
15 Wiper/washer module, body electronics control module
16 Data link
17 Data link DME
18 Starter
19 Service interval reset
20 Engine speed input RPM
21 Ignition switch to DME
22 Reversing light switch
23 Oil pressure
24 Instrument cluster, board computer
25 Alternator charge