W350 1 Ton Pickup 4WD V8-360 5.9L VIN 1 4-bbl (1988)
Fuel Gauge Sender: 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.