Tire Monitor System - 'Inoperative' Message Displayed
Date: April 27, 2009Order No.: P-B-40.15/67
Supersedes:
Group: 40
SUBJECT:
Model 171.454/456/458/473, MY 05-08 (with Telephone Kit Installed)
Model 209.456/472/477. MY 05-09 (with Telephone Kit Installed)
Display Message "Tire Pressure Monitor Inoperative"
If you receive customer reports in the above model vehicles of the instrument cluster displaying "Tire Pressure Monitor Inoperative" and there is a corresponding event code of A279 with the possibility of fault codes D162/163/164/165 being current and/or stored, this is caused by data transfer from the tire pressure system being disrupted by the MHI (Multiple Handset Interface) control unit. To resolve, shield component N123/1 (MHI control unit) as per the below steps.
This is caused by the radio signal of the tire pressure system being blocked by radio frequency noise from the MHI control unit.
1. Remove component N123/1 (MHI control module).
2. Check the cover of the N123/1 (MHI control module) and tighten if necessary.
3. Degrease the N123/1 (MHI control module) by wiping with brake cleaner. Do not spray directly on module.
4. Seal the three seams of the N123/1 (MHI control module) cover with the copper tape (Figure 1).
5. Route the wiring harness away from the N123/1 MHI control module (Figure 2 and 3).
6. Set tire pressures (cold) to the correct levels at ambient temperatures (outside/not in a heated workshop).
7. Clear fault and event codes.
8. Reactivate the TPMS system.
Parts Information
Note:
The following allowable labor operations should be used when submitting a warranty claim for this repair. This information has been generated on April 27, 2009. Please refer to Netstar --> Star TekInfo --> Star Time for the most current labor time allowance.
In Case of Warranty, use the table above.