DTC P1638, P1798 - Diagnosis Information
418-06DATE
1/98
V8 XJ Series/XK8
MODEL
1998 MY-ON XK8 Range
1998 MY-ON V8 XJ Series
VIN
018108-ON
812256-ON
Diagnostic Trouble Codes P1638 P1798 - Additional Information
Issue:
This bulletin provides additional information for use when diagnosing the following Diagnostic Trouble Codes (DTCs;):
P1638
P1798
Action:
When diagnosing the above DTCs, note the following information:
DTC P1638 CAN Link ECM/Major Instrument Pack Circuit/Network Malfunction
This DTC may be stored if the battery is reconnected with the ignition switch in position 2 - the normal engine running position.
Always ensure that the ignition switch is in position 0 (OFF) when disconnecting or reconnecting the battery.
DTC P1798 Major Instrument Pack Diagnostic Time-out
This code may be stored in the TCM, if DTCs in the Major Instrument Pack are cleared before clearing other codes present in the TCM, ECM, or ABS Modules.
Read and clear codes in the following order:
1. Read TCM/ECM/ABS DTCs
2. Read Major Instrument Pack DTCs
3. Clear Major Instrument Pack DTCs if required.
4. Clear TCM/ECM/ABS DTCs.