Speedometer Indication Erratic Or Needle Wavers Excessively

Verify condition, ensure speedometer is erratic or fluctuating. If speedometer is erratic or fluctuating, proceed to step 2).
Checking speed sensor connection, check speed sensor connection at the transmission. If connection is loose or defective, repair as necessary. If connection is good, proceed to step 3).
Checking speed sensor operation, replace speed sensor and road test vehicle. If speedometer operates okay, original speed sensor is defective. If speed sensor is still erratic, install original speed sensor and proceed to step 4).
Checking signal at connector plug, using ohmmeter, check continuity between pin No. 10 (Dark Green/White wire) of instrument cluster connector "A" and speed sensor while wiggling wiring. The instrument cluster connector "A" is the 14-pin connector on left side of instrument cluster as viewed from rear of instrument cluster.
Check for continuity between pin No. 11 (Orange/Yellow wire) of instrument cluster connector "A" and ground while wiggling wiring. Check for continuity between pin No. 12 (Red/Yellow wire) of instrument cluster connector "A" and 10-amp fuse No. 18. Fuse is located in fuse panel below left side of instrument panel.
If no continuity exists or is erratic, repair wiring as necessary. If continuity remains steady, proceed to step 7).
Checking printed circuit continuity, check for continuity between instrument cluster printed circuit and the following wire terminals of connector "A": Dark Green/White, Orange/Yellow and Red/Yellow.
If no continuity exists, replace defective terminals. If continuity exists, replace speedometer. Adjust odometer mileage on replacement speedometer and install odometer sticker on driver-door pillar to indicate speedometer replacement.