I've beenhaving intermittent starting issues (theft light blinking) with my 2000 Mountaineer. It used to only happen after a short 10 minute ride. I would stop the vehicle, do a quick errand, get back in, and then not be able to start it for up to 10 min. Icarry threeidentical (programmed and working) keys for theMountaineeron my key chainand keep alternating between them until one works. Eventually after trying the different keys in succession, the theft light would stay solid and then I would be able toturn the engine over. Lately, the problemoccursona cold start in the morning sometimes as well, which throws a curveball into the equation.

Last week the Mercury dealerdisconnected the 3rd party (Autopage) remote starter and replaced my transponder thinking that the remote starter caused the transponder to malfunction. This didn't appear to solve the problem. I brought it back in this past Monday and they replaced the PATS unit. This again did not solve the problem. As soon as I ran one errand after picking up the vehicle itfailed to start soI had to drop it off again at the dealer last night. The service rep is mystified.

Any idea what it could be? If the problem did not exhibit itself on a cold start you could make the argument that some electrical short is occuring due to the vehicle being driven and some thing getting heated up.