Help w/ '99 Trooper

I have '99 Trooper with "TOD". It has been runing great for the past 2 weeks, since I bought it, untill today... Does anyone have any idea why
the lights indicating my back two tires (in TOD section) and "CHEK" light are flashing. Two back tires are worn out quite a bit. Could that be it, or could it be something a lot more serious wrong with me back wheel drive? Any advice would be super-helpful. Thanks, Marko
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Interesting thing happened few hours later... I turned the Trooper on, wanted to drive it so someone can take a look at my problem. As I am driving to dealer, half way there, all the flashing stops and the car starts acting 100% normal. Turned around and just got some gas.... I am hoping it's just wiring
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I had the problem happen to me after buying the trooper used after 2 weeks. I also have a '99 Trooper and it was pretty easy to fix. I had come to the conclusion that it would most likely be 1 of 2 problems. The first and most likely problem is the TOD vacuum solenoid unit (which is mounted on the front axel under a splash shield) Try testing they unit while still attatched to the vehicle and running: One end of the solenoid pack should have a vacuum on it when the TOD button is pushed, and the other end should have a vacuum on it when the button is back to normal. You can try taking the unit off (remember where the vacuum hoses were plugged in) and try to clean them out- first with some compressed air, then with some WD-40, then with some compressed air again. Here is a website that someone put out there to help with your testing. Once you have the solenoid off, you can use a 9v battery to test the solenoids to see it the are switching the vacuum path correctly by blowing through the hoses.
http://www.lssolutions.demon.co.uk/Car/4wd.htm
The other problem (the one that I had, which I found after going through all the other stuff first because I didn't think to check it even though it was right in front of me) is the TOD position switch- may even be called a front axel position switch which is located also on the front axel next to the solenoid pack. I knew mine was bad because one of the two wires was broken off. In order to get it off, you must first drain the fluid out of the front differential, then unbolt the 4 bolts on the housing that the switch is mounted on, unbolt the old sensor/switch, and install new sensor/switch (with a new copper gasket for the sensor) remount the housing, plug in sensor/switch, and refill differential (being sure to add anti-slip differential additive).
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.