Hey everyone, I have a 2000 Jeep XJ with 145,000 miles on it. Last week my check engine light came on for the Code P1698 (No CCD messages received from the TCM), but the Jeep seemed to be running fine. I got it home, cleaned all the grounds, and did a hard reset on the computer. Took it on a two hour trip the next day, and it ran fine. I didn’t drive it for about 3 days and I went and drove it today. Check engine light came on, and almost immediately my battery voltage dropped to zero, the radio got staticky,and the check gauges light came on. Managed to get it to the parts store and had the code read, it was the same P1689. I was curious if it was maybe the alternator was going bad, so I had them test it and it was fine. Any ideas on what I can do next? Dealership wants 799 for a new ECM, along with 300 for labor, as well as 150 to flash it! Just as some background, alternator is 3 years old, and the battery is less than a year old! Also the transmission seems to be shifting well! Any help is appreciated! Thank you!