C 1500 Yukon 2WD V8-4.8L VIN V (2000)
Diagnostic Chart (Part 2 Of 2)
Schematic
CIRCUIT DESCRIPTION
The engine coolant level switch is located in the radiator surge tank. The engine coolant level switch is a float type switch. The Powertrain Control
Module (PCM) supplies a voltage to the engine coolant level switch. The engine coolant level switch is a normally open switch. When the coolant
level is within an acceptable range the engine coolant level switch closes. The switch opens when the engine coolant level drops below a
predetermined amount. When the PCM detects a high signal voltage, switch open, from the engine coolant level switch the PCM sends a Class 2
message to the Instrument Panel Cluster (IPC). The IPC displays the LOW COOLANT message.