03 lesabre wont start after ECU changed

[joncharette]

hey guys, I have an 03 lesabre that I bought almost two years ago and the fuel gauge quit on me after 1 week of owning it. I finally started doing some trouble shooting recently, and found that my ECU was malfuntioning and causing my fuel gauge to read 0. I went to a scrap yard and picked up another ECU and changed it out. The fuel gauge now works but the car wont start. I figure it has to do with the security system, so I tried resetting it from what I found on the internet, leaving the key on for 10 mins till the security light goes out and key off and try starting. I did this numerous time and its not helping. Any advise would be appreciated

 

[redmondjp]

Take it to a GM dealer to have the new ECM programmed. Each electronic module on the vehicle has the VIN encoded into its memory. Modules with non-matching VINs will not function. Welcome to modern automotive electronics!

If it makes you feel any better, my friend is working on a 2007 Taurus, and it requires exactly the same procedure when a replacement VIN is installed.

 

[joncharette]

ya oh the joys of moderm electronics! Thank you very much for the info, I`ll enquire with the dealer.

 

[Spriteman]

You might try removing the -NEG battery cable for 15 mins - turn the key while disconnected - then reconnecting. I'm not sure it will do anything but it might reset the PCM.

You might still wind up at the dealer.