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| ELECTRICAL – CHARGING SYSTEM – DTC P1246 – BATTERY WARNING LAMP ILLUMINATED – VEHICLES BUILT BEFORE 7/1/2002 |
| LINCOLN: | 2003 TOWN CAR |
2003 Town Car vehicles built before 7/1/2002 may exhibit a battery warning lamp illuminated with a diagnostic trouble code (DTC) of P1246 (Generator Load Input Failed) in the powertrain control module (PCM).
ACTION:
The condition may occur when the vehicle is started and immediately placed into gear and driven, without allowing the engine to return to normal idle.
Under these circumstances the PCM strategy will not command the alternator to charge, resulting in the illumination of the battery warning lamp and a P1246 DTC.
There is a revised PCM strategy available to correct this condition. Refer to the following service procedure for details.
SERVICE PROCEDURE
- Ensure that battery is fully charged.
- Inspect battery and generator connections to ensure they are secure. Correct as required.
- Reprogram the PCM to the latest calibration level using WDS or Ford J2534 B28.3 or higher.
For additional charging system information refer to Workshop Manual.
Service Information & Reprogramming
Software necessary to program electronic modules to the latest calibration level, perform module initialization (PATS), and set Programmable Parameters on Ford, Lincoln and Mercury vehicles.
Ford Module Programming (FMP) is a software application that allows subscribers to program electronic modules on Ford, Lincoln and Mercury vehicles. It can be used for:
- Reprogramming emission-related (OBDII) modules on some vehicles manufactured in 1995 and all vehicles manufactured from 1996 to the present
- Reprogramming or reconfiguring non-emission-related modules on many vehicles (UBP and MS-CAN not supported)
In addition, module initialization (PATS) functions such as Keycode Erase/Reprogram and PCM Parameter Reset can be done using this application.
J2534 Device 
using Ford Module Programming (FMP) can Reprogram and Configure most Modules.
Latest Calibration Information
Module Build Data (As-Built)
Use VIN to obtain As-Built data
