SDMO R33C3, User And Maintenance Manual

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F)-Fault finding module internal errors.
Like any equipment using internal memory and a program, the fault finding module generates fault codes. Two types of code can be
recognised:
- Address Claim Procedure Errors
- Run Time Bus Errors.
Address Claim Procedure Errors ( ACP-Err ):
The following fault codes relate to the switching on of the fault finding module.
Error Code 1:
When switched on, the fault finding module must issue a request to the ECU for the network addresses used in order to exploit them;
this screen appears when:
- an address cannot be used.
- the fault finding module cannot find the default addresses.
- an address cannot be found in the correct register.
Error Code 2:
Passive Bus Error: this code appears when:
- the fault finding module cannot detect the ECU: in this case the CAN Bus is open.
- the CAN_hi and CAN_lo run time bus connection is reversed between the source (ECU) and the fault finding module.
Error Code 3:
This code is the result of the following problems:
- the CAN_Hi or CAN_lo bus, or both, are connected to an electrical ground or an external source of current.
- data is being not transmitted at a standard baud rate.
This type of fault generally requires repairs to be carried out on the CAN BUS connection and therefore involves work on the engine
wiring harness, i.e. on the fault finding module extension.
Run Time Bus Errors:
Fault codes can only be active if the fault finding module has been able to obtain the network addresses when it was switched on, see
Address Claim Procedure Errors (ACP-err).
Error Code 1:
EP=Passive Error, this screen appears when the fault finding module loses contact with the ECU, there may be two causes of this:
- one connector on the bus connection is disconnected.
- the CAN Bus is open.
Error Code 2:
BO=Bus Off, in this case, the case is identical to Error code 3 of the ACP.
Error Code 3:
BR=Bus Reset, this error code is similar to Error code 3 of the ACP, as are its causes. In this case the fault finding module has
encountered problems on the CAN Bus and it tries to automatically re-establish the network connection.
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