D 150 Pickup V6-239 3.9L (1992)
Temperature Sensor (Gauge): Testing and Inspection
When a malfunction occurs with a cluster gauge, before disassembling the cluster to check the gauge, check for a defective sending unit or wiring as
follows:
1. Ground sending unit connector leads, at the sending unit, in the vehicle.
2. With ignition in ON position, a grounded input will cause the fuel or temperature gauge to read maximum or above.
