Tire Monitor - Tire Pressure Monitoring Inactive Message
Date: January 3, 2008Order No.: P-B-42.45/86
Supersedes:
Group: 42
SUBJECT:
All Model 171, 203 and 209 Vehicles
Equipped with Sales Code 477 - Tire Loss Warning System (indirect ESP based) with Run Flat Tires
Model Year: 2005 to 2007
"Tire Pressure Monitoring Inactive" Displayed in Instrument Cluster
If you receive customer reports in the above model vehicles with the message "Tire Pressure Monitoring Inactive" displayed within the instrument and the following fault code is stored within the ESP control unit, perform the following.
^ C1550 - Test voltage supply at control unit N47-5 (ESP and BAS control module)
Note:
This may result from an incorrect fault setting condition with the tire pressure loss warning software. If there is an under-voltage in the ESP control unit when writing to the EEPROM (Electrically Erasable Programmable Read-Only Memory) or if an ignition change occurs when the vehicle is moving, an invalid value can be supplied to the EEPROM check. This can produce fault code C1550 even if the ESP control unit is OK.
1. Check power supply (> 12 V) at component N47-5 (ESP control unit) and correct any connection issues.
2. Check ground connection of component A7/3 (Traction system hydraulic unit) and correct any connection issues.
3. Using STAR Diagnosis perform a short test and erase fault codes
4. Cycle ignition on-off-on
5. Using STAR Diagnosis recheck for the above fault codes within ESP.
6. If no fault code is present the ESP control is OK.
7. If the fault code listed above is present, replace the ESP control module. Refer to ESP for latest part number. ESP control unit replacement is only justifiable if the fault is currently stored and there is no under-voltage present at the ESP control or hydraulic unit.
Note:
The following allowable labor operations should be used when submitting a warranty claim for this repair. This information has been generated on January 3, 2008. Please refer to Netstar --> Star TekInfo --> Star Time for the most current labor time allowance.
In Case of Warranty, use the table.