Clock modules occasionally suffer from faint displays, caused by bad contacts between a circuit board and flexible ribbon cable inside the unit. It is possible to make a repair, though some may consider it to be a less than professional fix
Remove the connector at the rear of the clock unit itself, undo the four screws attaching it to the rest of the assembly and then take it to a bench area for further work.
The unit itself is opened by undoing the small screws at the rear and releasing the plastic tabs. Whilst the unit is open, take care not to lose any of the small components in there. Release the LCD panel itself by carefully spreading the black tabs holding it into the white plastic bracket. The panel is attached to the main circuit board by a ribbon cable, and it is the connection at the circuit board end that is the problem.
Tape the ribbon cable in place and use a business card or piece of pizza box ( both have been successfully deployed! ) to put pressure on the ribbon cable where it connects to the pcb, behind the white plastic bracket.
Take the unit to the car in plug it in. Use the time set buttons to cycle through all the digits to make sure the fix is complete before reassembly. If segments are still missing or faint, additional pressure may be needed on the ribbon cable.
When all is working, reassemble the clock unit and then refit into the centre console. Attach the cable and take care not to stress any other wires as you fit the console back into position.
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Hope this helps Regards Derek
1995 XJR Poole Dorset