Radiator Cooling Fan Motor Relay: Description and Operation

DESCRIPTION
Since the engine cooling fan system is computer controlled, the Constant Control Relay Module (CCRM) and the Powertrain Control Module (PCM) control the cooling fan during vehicle operation.

OPERATION
The CCRM and the PCM will energize the cooling fan under the following conditions:
1. The cooling fan is turned on low speed if:
a. Engine temperature is higher than normal. (Fan starts running at 102° C (215° F) and stops running at 99° C (210° F).
b A/C is on and vehicle speed does not provide enough natural airflow. (Fan starts running at speeds at or below 69 km/h (43 mph) and stops running at 77 km/h (48 mph).

NOTE: Normal operation and cycling of the engine cooling fan will cause the temperature gauge indicator to read between the mid-point and upper portion of the temperature gauge scale. The slightly higher indicator reading will return to mid-point when fan operation begins.

2. The cooling fan will run at high speed if:
a. Engine temperature is higher than desirable and fan has been operating at low speed. Fan starts running at high speed at 110° C (230° F) and stops running at 107° C (224° F).