LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Saturn >> 2000 >> LS2 Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0480: Cooling Fan Control Relay No. 1 Circuit >> Diagnostic Procedures
July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD system check, go to next step.
  2. Turn ignition on, with engine off. Using scan tool, command fan control relay No. 1 on and off. If cooling fans follow command (medium speed), problem is intermittent. See DIAGNOSTIC AIDS . If cooling fans does not follow command, go to next step.
  3. Disconnect cooling fan control unit harness connector. Connect a test light between battery voltage and cooling fan control unit harness connector terminal "F" (Dark Green wire). Using scan tool, command fan control relay No. 1 on and off. Observe test light. If test light does not turn on, go to next step. If test light follows scan tool command, check for terminal tightness. Repair as necessary. If terminals are okay, replace cooling fan control unit. If test light stays on, check Dark Green wire for short to ground. Repair as necessary. If circuit is okay, replace ECM.
  4. Using a DVOM, check voltage at cooling fan control unit harness connector terminal "F" (Dark Green wire). If voltage reading is greater than 4 volts, check for short to voltage in circuit (Dark Green wire). Repair as necessary. If circuit is okay, replace ECM. If voltage reading is 2-4 volts, replace ECM. If voltage reading is less than 2 volts, go to next step.
  5. Check for open in Dark Green wire to ECM. Repair as necessary. If circuit is okay, check for terminal tightness. Repair as necessary. If terminals are okay, replace ECM.
scientia non olet · About LEMON Manuals