Just returned from my local dealership and wanted to share a new TSB for '12 and '13 Pilots.
Symptom: A humming or groaning noise is heard at idle when the A/C cycles on.
Cause: When the AC compressor and the power steering pump run simultaneously, they sometimes create a natural harmonic that travels through the vehicle's body, which can be heard as a groan in the passenger compartment.
Corrective Action: Replace the power steering pump and power steering bracket.
Symptom: A humming or groaning noise is heard at idle when the A/C cycles on.
Cause: When the AC compressor and the power steering pump run simultaneously, they sometimes create a natural harmonic that travels through the vehicle's body, which can be heard as a groan in the passenger compartment.
Corrective Action: Replace the power steering pump and power steering bracket.