| All values measured to ground unless otherwise noted | |||
| A1 | |||
| 1A.14 | Voltage coded signal input from horn switch and multi fuction buttons in steering wheel | No reliable test | Use SDS to test |
| 1A.15 | Voltage coded signal input from horn switch and multi fuction buttons in steering wheel | No reliable test | Use SDS to test |
| 1A.18 | Voltage coded signal input from horn switch and multi fuction buttons in steering wheel | No reliable test | Use SDS to test |
| Voice recognition system activation / deactivation | Ignition on | ||
| 2D.1 | Ground signal output | ||
| 2D.2 | switched ground signal input | measure to pin 2D.1 > 1 VDC | switch not activated |
| 2D.3 | switched ground signal input | measure to pin 2D.1 > 1 VDC | switch not activated |
| 2M.1 | CAN-Bus (high side). High speed data transfer bus input and output, shares data with radio or COMAND | No reliable test. Check continuity to other ECMs | Use SDS to test |
| 2M.2 | CAN-Bus (low side) | ||
| A2 | |||
| A.4 | Circuit 30 power input | 12 VDC at all times | Feed from F1f10 |
| A.7 | Circuit 15R power input | Ignition on 12 VDC | Feed from F1f3 |
| A.8 | Main ground to W19 | Approx. 0 Ohms to ground | |
| C.1 | CAN-Bus (low side). High speed data transfer bus input and output, shares data with IC | No reliable test. Check continuity of wiring | Use SDS to test |
| C.2 | CAN-Bus (high side) | See pin C.1 | |
| C.4 | "Wake-up" signal input | No reliable test | |
| D2B IN D2B OUT |
Optical input port Optical output port |
No reliable test | |
| A2/31 | |||
| Antenna amplifier interchanging signals | No reliable test, check continuity of wiring | ||
| A34/6 | |||
| 1.1-10 | Handset to audio module interchanging signals | No reliable test, check continuity of wiring | |
| A59/1 | |||
| 1.3 | Main ground to W6 | Approx. 0 Ohms to ground | |
| 1.4 | Circuit 30 main power input | 12 VDC at all times | Feed from F1f7 |
| 1.5 | Circuit 15R power input | 12 VDC with key in position "1" | Feed from F1f6 |
| 1.13 | Wake up signal input | No reliable test | |
| 1.14 1.15 |
Hands free microphone signal input low side and shield high side |
No reliable test, check with test microphone | |
| 1.20 | Shield connection | Note 1 | |
| D2B IN D2B OUT |
Optical input port Optical output port |
No reliable test | |
| Note 1 | Phone systems are replaced as whole unit and do not require further maintenance | Check for proper power supply and continuity of wiring | |