4wd Lights Flashing

[mjd]

My 99 XLS with V6 OHV, auto, and Control Trac started flashing the 4Hi & 4Lo lights yesterday. They flash 6 times, then stop for a couple of minutes, then do it again. The switch is set to Auto, and 4wd is working (muddy roads to verify that with), and appears to be in Auto mode (no binding in turns). The switch won't do anything now. From reading through previous posts, it looks like the problem may be a speed sensor, or the motor on the transfer case. How do you test the sensors, and can you get to them w/o disassembling the transfer case? I'm going to try disconnecting the battery to see if it will clear anything, but haven't had a chance to do that yet. Any suggestions or help would be appreciated.

thanks,
Murray

 

[TPLYNCH]

6 flashes, repeated I'm fairly certain is the speed sensors. If you can shift into 4Lo, then it is not your shift motor. The sensors are just magnets that plug into the transfer case. The plug may have come loose, or the sensor may just be dirty. You don't have to remove the t/f case to check/clean them, although the front one is a b***h to get to.

P.S. Welcome to the site!

 

[dwnthehatch]

MY 97 explorer did the same thing. It was the speed sensor. My 98 expedition also had the same problem and solution.