Use this procedure to troubleshoot any suspect problems with the engine coolant level sensor.
The engine coolant level sensor provides a means of monitoring the engine coolant level in order to warn the operator when the coolant level is low. The engine coolant level sensor is located in the top tank of the radiator. The sensor should be immersed in coolant at all times.
When the sensor is immersed in coolant, an internal switch is closed. When the internal switch closes, the signal for the engine coolant level is grounded through the sensor return. The Electronic Control Module (ECM) detects the ground on the input for the engine coolant level. If the signal is not present, an event code is generated.
Verify that the coolant level has been programmed to “Enabled” on the configuration screen on the Cat® Electronic Technician (ET). If the coolant level is not programmed, Cat ET will display “Unavailable” for the parameter.
Illustration 1 g03729968
Schematic of the engine coolant level sensor
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Engine components for the engine coolant level sensor
(1) P61 customer connector
(2) J1/P1 connectors
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Rear view of a typical radiator with an engine coolant level sensor
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P1 terminals that are associated with the engine coolant level sensor
(P1-4) +8 VDC (digital sensor supply)
(P1-49) Engine coolant level
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J61 and P61 terminals that are associated with the engine coolant level sensor
(8) +8 VDC (digital sensor supply)
(36) Engine coolant level