Cherokee 2WD L6-242 4.0L VIN M FI (1987)
Vehicle Speed Sensor: Testing and Inspection
Fig. 8 Speed sensor connector terminal identification
1. With engine at operating temperature, disconnect speed sensor electrical connector from ignition control module.
2. Connect a suitable ohmmeter between connector terminals A and B, Fig. 8.
3. Ohmmeter should indicate 125 to 275 ohms, if not replace sensor.