Symptoms

- Engine Light ON (or Service Engine Soon Warning Light)

Possible Causes

- New PCM-Needs programing - Incorrect VID configuration

Tech Notes

After a new PCM has been installed, the Vehicle Identification (VID) block has to be program to the PCM. There is a service bulletin for the P1639 code for the following models: 2002 MERCURY MOUNTAINEER Service Bulletin Code P1639

Description

Vehicle ID block is not programed or is corrupt