Trouble Shooting
- Perform QUICK TEST to retrieve any cooling fan related codes. During QUICK TEST, 3 types of diagnostic trouble codes are retrieved: KOEO, KOER and Continuous Memory codes. See appropriateG - TESTS W/CODES article in ENGINE PERFORMANCE section listed below:
- If any cooling fan related codes are present, identify code and go to appropriate step. See CONSTANT CONTROL RELAY MODULE RELATED CODES table. If no codes are present, connect NGS scan tool to Data Link Connector (DLC).
- Turn ignition on. Access Output Test Mode on NGS scan tool. Command cooling fan on and check fan operation. On models with 2 fan speeds, check both fan speeds. On all models, if fan does not operate properly, perform appropriate test. See TROUBLE SHOOTING DIRECTORY table.TROUBLE SHOOTING DIRECTORY
Application Go To Step Fan Always Runs (1) 80 Fan Inoperative (1) 40 (1) Perform appropriate step under CONSTANT CONTROL RELAY MODULE (CCRM) .