Instruments - Erratic Operation
413-04DATE
2/99
V8 XJ Series/XK8
MODEL
1997-98 MY XK8 Range
1998 MY V8 XJ Series
VIN
001001-029371
812256-848623
Erratic Operation - Instruments -
Repair Procedure
Issue:
On V8 XJ Series and XK8 vehicles, the speedometer, tachometer, fuel and temperature gauges each receive signals through ribbon cables from the master printed circuit board of the instrument pack.
On vehicles within the above VIN ranges, the following symptoms may be caused by loose or disconnected ribbon cable connectors:
^ Needle erratic/wavering. Gauge indication possibly excessively high. - Connector loose.
^ Gauge needle stationary. Needle may be in an unusual position if the connector was loose before complete disengagement. - Connector disconnected.
Modified connectors were introduced from XK8 VIN 029371 and V8 XJ Series VIN 848624 to prevent ribbon cable connectors from becoming loose or detached.
Action:
In the case of any of the above symptoms, on V8 XJ Series and XK8 vehicles within the above VIN ranges, check that the ribbon cable connectors are firmly connected at the master printed circuit board before replacing any component.
1. Disconnect the battery negative cable. Follow the procedures detailed in JTIS to remove the instrument pack. Refer to JTIS Group 4, Section 413-01, Removal & Installation, SRO: 88-20-24.
2. Place the instrument pack on a clean work surface, on an antistatic mat, with the technician's body connected to ground by a wrist strap.
Caution:
Use great care during the next operations on the instrument pack.
3. Remove the 6 screws arrowed in Illustration 1, and remove the back plate from the instrument pack to gain access to the ribbon cable connectors.
4. Refer to Illustration 2. Check the connector of the appropriate ribbon cable for a secure fit at the master printed circuit board.
5. Reinstall the back plate and its securing screws.
6. Reinstall the instrument pack to the vehicle, but without installing the retaining screws.
7. Reconnect the multiplug connector to the main vehicle harness.
8. Reconnect the battery negative cable. Switch on the ignition. Check the operation of the gauges.
9. If the gauges now operate correctly, switch off the ignition and complete the reinstallation of the instrument pack.
10. Should a fault still exist, the problem may be within the instrument pack requiring replacement of the pack. Refer to the VCATS label to determine the correct part number of the instrument pack. Disconnect the battery negative cable before disconnecting the multiplug connector prior to removal of the suspect instrument pack.
Parts Information:
Refer to the VCATS label for the correct part number. Refer to technical bulletin 418-03 Amended 4/98 for the location of the VCATS label.
Warranty Information: