Check Engine Light - Reporting and Erasing DTCs
18-32Check Engine Light - Reporting and
Erasing Diagnostic Trouble Codes -
Use Correct Procedure
MODEL:
Sedan, XJS
Date:
7/93
ISSUE:
When the "CHECK ENGINE" warning light is on it is possible that more than one Diagnostic Trouble Code (DTC) is stored.
Disconnecting the vehicle battery or ECM to erase a displayed code will cause other stored engine management trouble codes to be lost.
Removing fuses to erase a displayed engine management DTC can cause transmission trouble codes to be stored.
ACTION:
When the "CHECK ENGINE" warning light is on, use one of the following two methods to report and erase the diagnostic trouble codes.
Method 1:
^ Connect JDS through the data link connector. Select Engine Management - Fault Diagnosis. JDS will display all stored codes.
JDS will then enter the diagnostic routine. If JDS asks "Do you wish to repair the fault?", answer "Yes".
At the end of the routine, JDS will erase the tested code.
Method 2:
^ Switch the ignition on. On sedans, press the VCM button to display a code. On XJS, a code is automatically displayed 5 seconds after the ignition is switched on. Record the code.
Locate the DTC reset connector:
90 MY - onwards Sedan: Red male Econoseal - K/R wire, located behind the passenger side underdash panel.
92 MY - onwards XJS: Purple male PM5 - Y/G wire, located behind the passenger side center console footwell panel.
To erase the displayed code, connect the wire in the reset connector to ground for 3 seconds.
Check for additional stored codes after the displayed code is erased by switching the ignition off for 5 seconds and repeating Method 2.
NOTE:
If a Diagnostic Trouble Code cannot be erased or returns when the vehicle is operated, the fault is still present.
Refer to the XJ6/XJ12 or XJS Service Manual Section 17 for DTC descriptions and diagnosis.