Bus and Diagnostics Communication: Overview Saab 9-3 II

Scheme 1

1. Engine Control Module, ECM (589/595/705/608)
2. Control module, TCM (502)
3. Underhood Electrical Centre, UEC (342)
4. Control module, AHL (664)
5. Control module, ESP/TCS (671/382)
6. Angle Sensor, yaw, YRS (658)
7. Control panel, infotainment, ICM (736)
8. Column Integration Module, CIM (703a)
9. Unit, power steering system, EHPS (745)

Scheme 2

1. Column Integration Module, CIM (703a)
2. Rear Electrical Centre, REC (701)
3. Control module, parking/auxiliary heater, PHM/AHM (597a)
4. Door control modules, DDM/PDM/RLDM/RRDM (702)
5. SPA control module (630)
6. Sun Roof Module, SRM (182b)
7. Main instrument unit, MIU (540)
8. Airbag Control Module, ACM (331)
9. Control module, BCM (707)
10. Shift Lever Module, SLM (726)
11. Driver Seat Module, DSM (357Dk)
12. Underhood Electrical Centre, UEC (342)
13. Control module, ACC (216)
14. Control panel, infotainment, ICM (736)

Scheme 3

1. Column Integration Module, CIM (703a)
2. Rear Electrical Centre, REC (701)
3. Park Heater Module, PHM (597a)
4. Control module, door, DDM/PDM (702D/P)
5. Control module, rear window lift, RLDM/RRDM (575RR)
6. SPA control module (630)
7. Main instrument unit, MIU (540)
8. Airbag Control Module, ACM (331)
9. Control module, BCM (707)
10. Shift Lever Module, SLM (726)
11. Driver Seat Module, DSM (357Dk)
12. Underhood Electrical Centre, UEC (342)
13. Control module, ACC (216)
14. Tyre Pressure Monitoring Module, TPMM (753)
15. Control panel, infotainment, ICM (736)
16. Control module, STC (565)

Scheme 4

1. Control panel, infotainment, ICM (736)
2. Entertainment head unit, EHU (353)
3. CD player/changer, front, CDF/CDCF (355F)
4. CD Changer Rear, CDCR (355R)
5. Audio System Amplifier, front speakers, AMP1 (354F)
6. Audio System Amplifier, rear speakers, AMP2 (354R)
7. Communication unit, Positioning unit, CU/PU (468/635)
8. Unit, DVD (729)

Scheme 5

1. Control panel, infotainment, ICM (736)
2. Entertainment head unit, EHU (353)
3. CD player/changer, front, CDF/CDCF (355F)
4. CD Changer Rear, CDCR (355R)
5. Audio System Amplifier, front speakers, AMP1 (354F)
6. Audio System Amplifier, rear speakers, AMP2 (354R)
7. Communication unit, Positioning unit, CU/PU (468/635)
8. Unit, DVD (729)

Scheme 6

1. Control panel, infotainment, ICM (736)
2. Entertainment head unit, EHU (353)
3. CD player/changer, front, CDF/CDCF (355F)
4. CD Changer Rear, CDCR (355R)
5. Audio System Amplifier, front speakers, AMP1 (354F)
6. Audio System Amplifier, rear speakers, AMP2 (354R)
7. Communication unit, Positioning unit, CU/PU (468/635)
8. Unit, DVD (729)

Scheme 7

The bus is divided into a

1. P-bus (Powertrain bus)
2. I-bus (Instrument bus)
3. O-bus (Optical bus).

A control module sends a message by sending ones and zeros in a predefined order. The control module only sends a message if no other control module is presently sending. The meaning of the combinations of ones and zeros is predefined so that all the control modules can interpret the information in the same way. The message contains information about what is being sent and the value, for example "Coolant temperature" 100°C or "A/C ON".

Scheme 8

The data link connector can access both the P-bus and the I-bus. With an adapter, Tech2 can be connected to the data link connector and can communicate with the different control modules on the P-bus and I-bus. Diagnostic communication with the control modules on the O-bus occurs via the ICM, which functions as a "gateway".

Certain information sent by a control module is made available to all other bus control modules. The CIM relays information between the I-bus and P-bus. The ICM makes sure that information available on the I-bus and P-bus is available on the O-bus, and vice versa.

See also:
• 4D