Chevrolet Sonic Repair Manual: Cooling Fan Description and Operation (LWE, LUW)
System Overview
The engine cooling fan system is composed of one cooling fan, 2 relays, the engine control module (ECM), and the associated wiring. The cooling fan assembly includes 1 resistor mounted in the cooling fan shroud. The cooling fan resistor may be a stand alone component, or a part of the cooling fan motor and harness assembly. This combination of components enables the ECM to operate the cooling fan at 2 speeds using two fan control circuits. The ECM will operate the cooling fan at either Low or High speed based on the cooling requirements.
Low Speed Operation
The ECM applies ground at the FAN 1 control circuit for the coil side of the low speed cooling fan relay. The energized low speed relay switch closes to supply B+ through the cooling fan resistor, to the engine cooling fan motor. The result is cooling fan operation at a reduced speed.
High Speed Operation
The ECM applies ground at the FAN 2 control circuit for the coil side of the cooling fan high speed relay. The energized high speed relay switch closes to supply B+ directly to the engine cooling fan motor, by-passing the cooling fan resistor. The result is cooling fan operation at full speed.
Cooling Fan Description and Operation (LUV)
The engine cooling fan system is composed of one cooling fan, a series of 5 relays,
the engine control module (ECM), and the associated wiring. The cooling fan assembly
includes two resistor ...
Engine Coolant Fan Shroud Replacement (LDE LUW)
Engine Coolant Fan Shroud Replacement
Callout
Component Name
Preliminary Procedure
Remove the radiator surge tank. Refer to Radiato ...
Other materials:
Front Side Door Trim Replacement
Front Side Door Trim Replacement
Callout
Component Name
Preliminary Procedure
Remove the front side door upper front trim panel. Refer to Front Side
Door Upper Front Trim Panel Replacement.
1
Fr ...
Battery Positive and Negative Cable Replacement
Removal Procedure
Disconnect the negative battery cable. Refer to Battery Negative Cable
Disconnection and Connection.
Remove the fuse block and battery positive cable cover.
Remove the battery tray. Refer to Battery Tray Replacement.
Remove the battery posit ...
Inspection/Maintenance (I/M) System DTC Table (LWE)
Inspection/Maintenance (I/M) System DTC Table
System
DTCs Required to Set System Status to YES
If an inspection/maintenance system status indicator did NOT update to
YES during the Inspection/Maintenance System Check,
review ea ...
0.0067