Data Link Connector
The vehicle is supplied with numerous electronic control units that perform a self diagnosis function. Connecting to these control units via diagnostic equipment allows you to read the self-diagnosis information (parameters, errors) or carry out available active diagnostics. All the diagnosis circuits flow into the European On Board Diagnosis (EOBD) connector which conforms to Directive 98/69/EC - ISO standard J1962 - located under the dashboard near the Body Control Module (BCM). On the same connector it is possible to diagnose all nodes (control units) connected both to the low transmission speed CAN-BH (IHS) bus for the management of standard body functions and to the high-transmission speed CAN-C1 (C) and C2 (CH) buses for dynamic vehicle controls (bus CAN-High and CAN-Low).
The 4x4 control unit also has an additional diagnosis connection, located next to the control unit itself.
DLC multiple diagnosis connector
The three networks are positioned in the multiple diagnosis connector in the following pins:
- Pin 3 - CAN-BH (IHS) High
- Pin 11 - CAN - BH (IHS) Low
- Pin 12 - CAN-C2 (CH) High
- Pin13 - CAN-C2 (CH) Low
- Pin 14 - CAN-C1 (C) Low
- Pin 6 - CAN-C1 (C) High
DLC multiple diagnosis connector position
Digital network voltage levels
CAN-C1 (C)
CAN-C2 (CH)
CAN-BH (IHS)
The CAN-C1 (C), CAN-C2 (CH) and CAN-BH (IHS) enter Sleep mode approximately 10-12 seconds after the key is turned to OFF. The networks "wake up" with the key at OFF when one of the vehicle's doors passes from "Closed" status to "Open" status.
The ACC module is connected to the HaLF module via a dedicated CAN data bus. The reason behind the dedicated data transmission circuit between the two modules is the continuous exchange of information between them during operation of the cruise control and of the FCW function.
Electrical continuity of the networks
The three digital networks CAN-C1 (C), CAN-C2 (CH) and CAN-BH (IHS) have 120-ohm terminal resistors. The electrical continuity of the networks can be checked directly via the diagnosis connector by setting the multi-meter to the Ohm function. When the network is electrically continuous, the value that the operator needs to read on the display is approximately 60 ohms for all three networks.
The central diagnostic socket receives a direct battery power supply from the circuit protected by a fuse located in the BCM. The BCM receives a direct power supply from the battery through the circuit protected by maxi fuse in the Battery Distribution Unit. The BCM receives an ignition-operated power supply (INT). This signal is used, among other things, to "wake up the network".