Component Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2011 GMC Yukon XL, 2011 GMC Yukon, 2011 Chevrolet Tahoe, 2011 Chevrolet Suburban, and 2011 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the cooling fan relay.
- Test for 50-90 Ω between terminals 85 and 86.
- If not within the specified range, replace the cooling fan relay.
- Measure the resistance between the terminals listed below:
- 30 and 86
- 30 and 87
- 30 and 85
- 85 and 87
The DMM should display OL.
- If less than the specified range, replace the cooling fan relay.
- Test the Fan Control Relay for less than 2 Ω between terminals 30 and 87A.
- If greater than the specified range, replace the cooling fan relay.
- Connect a 20 A fused jumper wire between relay terminal 85 and B+. Connect a jumper wire between relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.
- If greater than the specified range, replace the cooling fan relay.