Instrument panel connectors on 97+ are known to become intermittent. take the cluster out and clean the contacts with aerosol contact cleaner. Apply small amount of silicone grease to contacts and reinstall.
1992 XJ 2" lift -- RIP
2000 XJ 3" lift -- Australian Ford Big Brakes up front, rock rails, ZJ rear discs (with WORKING parking brake), C4x4 rear bumper/tire carrier, Hella H4 headlights, IPF driving lights, OEM skid plates, OME springs/shocks, JKS LCA's, JKS Sway Bar links.