| Subject: | Hum or Fan Noise From Navigation Radio |
| Models: | 2003-2006 Cadillac Escalade, ESV, EXT |
| 2005-2006 Chevrolet Suburban, Tahoe |
| 2005-2006 GMC Yukon, Yukon XL, Yukon Denali and Yukon Denali XL |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Customers may comment of a hum or fan running type noise from the navigation radio.
Recommendation/Instructions:
This noise is normal. Please do not replace the radio for this concern. The navigation radio has an internal cooling fan to cool the radio's internal components.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
