Group 87 Climate Control, Fault Codes
Troubleshooting
MID 146 SID 250 J1708 Information Link
General information
Diagnostic signals along with general information are sent
on the SAE J1587/1708 data link. In case of failure this
information link serves as a back up to the SAE J1939
control data link. The status of the vehicle is constantly
kept updated on the SAE J1587/1708 and is available to
be read via the diagnostic connector.
On the control link SAE J1939 the system’s control
signals are sent.
Fault code
FMI 9
Abnormal update rate
Conditions for fault code:
•
An fault code is stored if information about the vehicle
speed is not received on the SAE J1708 data link
within 60 seconds.
•
An fault code is stored if information about the engine
speed is not received on the SAE J1708 data link
within 60 seconds.
•
An fault code is stored if information about the engine
coolant temperature (ECT) is not received on the SAE
J1708 data link within 60 seconds.
Possible cause:
•
Faulty control unit
•
Datalink congestion
Reaction from the control unit:
•
Fault code is stored
•
Yellow lamp requested
Noticeable external symptoms:
•
Yellow lamp lights up
•
Limited function in the climate control unit
appropriate check:
•
Fault-trace the SAE J1708 data link, see service
information group 371 ”Data links, fault-tracing”.
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