1456 / 1906
ELECTRICAL
154
IVN DIAGNOSTIC TROUBLE CODES:
Three types of IVN DTCs are present.
Message Time-Out Error
Missing message Error
Communication Bus-Off error (
One DTC
against itself
)
Exception:
ABS/ESP does not log missing message DTCs.
FATC ECU only receives data so do not log
communication bus-off DTC. Its log only
missing message & message timeout DTCs.
ABS logs CAN communication bus open error.
IVN FAILURES:
Following are the list of failures of the CAN
network
Short circuit failures in the harness
1. CAN_H and CAN_L short circuit
2. CAN_H and GND short circuit
3. CAN_L and GND short circuit
4. CAN_H and Vbatt short circuit
5. CAN_L and Vbatt short circuit
Open circuit failures in the harness / Connector
1. Open circuit in the main CAN bus
2. Loose connection near ECU connector
due to MTO or TBO.
3. Permanent open circuit in any of the CAN
stubs.
4. Temporary open circuit in any ECU
connector.
Permanent failure of ECU’s.
Temporary failure of ECUs (
due to SW locks
).
DIAGNOSTIC GATEWAY
Instrument Panel Cluster (IPC) is the Diagnostic
Gateway.
Diagnostic Gateway is used to prevent the Main
vehicle CAN bus from external noise and
unauthenticated/ mischievous tools from creating
nuisance on the Main CAN bus.
All IVN DTCs shall be read through the Diagnostic
Gateway i.e Diagnostic tester shall be connected
to Diagnostic Gateway which shall route the tester
request message to the corresponding ECU and
then also route the ECU response back to the
tester.
IVN DTCs IMPLEMENTED
1. Lost Communication:
Bus signal/message failure DTC: Logged when the
message is not received from the partner ECU. It
is mainly due to partner ECU not connected or not
powered up properly
2. Vehicle Communication Bus A:
Error Passive / Open Circuit DTC: Logged due to
open/short circuit failures in CAN bus. This DTC
will be seen as history in all ECUs with CAN
diagnostic except the diagnostic gateway (IPC)
and K line ECUs
3. Vehicle Communication Bus A:
Bus Off DTC: Logged due to open/short circuit
failures in CAN bus. This DTC will be seen as
history in all ECUs with CAN diagnostic except the
diagnostic gateway (IPC) and K line ECUs.
4. Invalid Data received:
Invalid Data DTC: This DTC is logged when the
partner ECU sends implausible/incorrect value for
any of its signal
5. Invalid Data received:
MRC DTC: This DTC is logged when the partner
ECU does not send continuous updated data. This
DTC will be seen as historic (most of the times)
6. Invalid Data received: CRC DTC:
This DTC is logged when the partner ECU does
not send the correct checksum of critical signals.