Table 1. 247 SAE J1939 Data Link Diagnostic Codes.
CID FMI CODE
TEST OR INSPECTION
247-9 SAE J1939 Data Link
Abnormal Update Rate
· Always inspect wiring harness connectors that are involved in the circuit.
Poor connections can often be the cause of a problem in an electrical
circuit. Verify that all connections in the circuit are clean and secure and
that all connections are in good condition. If a problem with the
connection is found, correct the problem and verify that this malfunction
or diagnostic code is active before performing this procedure.
· Perform open or short-circuit test at each wiring harness connection to
identify the correct wiring harness to replace.
· Tag all wiring harnesses to aid in installation.
· Perform this test only if condition is active.
DIAGNOSTIC CODE SET CONDITION
Engine ECM detects another controller has stopped transmitting a J1939 speed
request (TSC1) incorrectly or another controller has started transmitting a J1939
speed request incorrectly.
· CAN data link 1 resistor is open.
· CAN data link 2 resistor is open.
· Lower cab wiring harness high resistance or open.
· Engine wiring harness shorted.
· Lower cab wiring harness shorted.
Test Step 1. Check for Active
1. Connect MSD and select C6.6 924
2. Start engine or attempt to start
Diagnostic Code 247-9 Active -
engine (TM 5-3805-298-10) while
Proceed to Test Step 2.
using MSD to check for active
Diagnostic Code 247-9 Not Active -
Troubleshooting is complete.
Test Step 2. Test CAN Data Link
Circuit for Terminating Resistance.
1. Turn ignition switch and battery
disconnect switch to OFF position