A/C - Rear Seat Fans Make Rattling/Grinding Noises

DTB

Date: October 2, 2008
Order No.: P-B-91.30/121a
Supersedes: P-B-91.30/121 dated Nov. 22, 2006
Group: 91







SUBJECT: Model 221.171/176/177/179/186
Equipped with Rear Seat Climate Control (Code 402)
Active Seat Cushion Ventilation Fans in Rear Seats Making Rattling / Grinding Noise

If you receive customer reports in the above model vehicles regarding the active seat cushion ventilation fans in the rear seats making a rattling or grinding noise, this may be due to the fan impeller contacting the seat cushion base.

1. With the seat ventilation fans activated, analyze source of the noise while changing the pressure distribution or load on the individual rear seat cushions.

2. If the fan impeller(s) contact the rear seat cushion frame, a grinding noise will be audible. Remove the rear seat cushion assembly, refer to WIS document AR91.12-P-1020SX.

3. Remove the seat cushion leather and seat cushion foam pad from the seat cushion frame, refer to WIS document AR91.18-P-1850SX. Complete steps 1 to 5 only, do not separate the leather from the foam pad.

4. The two cutouts in the rear seat cushion frame (Figure 1, 2) need to be modified. The original shaped cutouts (Figure 1, pos 2) must be modified (Figure 1, Pos 3).







5. Using a file or small grinder, remove the high points of the two cutouts in the area marked in red (Figure 2). The dimensions are shown (Figure 3).










NOTE: Steps 4 and 5 of this repair is non-time claimable under Group 91.

6. When completed, the fan impeller(s) will no longer contact the seat cushion frame (Figure 3).

7. Reinstall the rear seat cushion to the cushion frame, refer to WIS document AR91.18-P-1850SX.

8. Reinstall the rear seat cushion assembly, refer to WIS document AR91.12-P-1020SX.

NOTE: The following allowable labor operations should be used when submitting a warranty claim for this repair. This information has been generated on October 2, 2008. Please refer to Netstar -> Star TekInfo -> Star Time for the most current labor time allowance.

In Case of Warranty

Operation: Rear seat cushion - l/side, R&R (91-5058)
Rear seat cushion - r/side, R&R (91-5063)
Modify seat base (91-0000)