There is a small plastic gear in the gauge cluster that is prone to failure. Buy a set (2 parts, 1 each) here and replace it. This requires removing some trim but is a reasonable ~3 hour project for most DIY people. I'm assuming you have an analog gauge.
Good luck.
Replace the flasher relay if none of them are working.
How do you replace the timing chain on a 1994 mercury grand marquis
how do i replace a passenger side headlamp for a 2004 grand marquis gs
2004 mercury grand marquis fan stop working
how do you replace the front sway bar likn in a 1999 Grand Marquis?
how to replace starter on 2000 mercury grand marquis
how do you get to and replace the wiper moter on a 97 marquis
troubleshoot head lamps on 1988 grand marquis? Not working...fuses OK
i have no heat in my 1994 mercury grand marquis. what could cause the heat to stop working
A 1993 Jeep Grand Cherokee does not have a speedometer cable. The speedometer signal comes from a sensor on the transmission or transfer case.
take it to a shop
alot