troubleshooting where to start?

This site has been a wealth of info and has directed me to some other good installation and wiring diagram sites to assist me; however, I still have an issue.

Vehicle: 2005 Dodge Grand Caravan
Remote Starter Model: Ultra 1355A

This model was already installed in the van before we bought it and only now has it ever had issues. Up until a month ago, it stopped responding to remote inputs so we replaced the batteries. Oddly enough, when following the polarity indicators in the remote to install the battery, the LED doesn't light up. On a whim, I turned the battery around, opposite to what the indicators suggest, and the LED works fine.

The major problem? At random times, whether the van is running in park, while driving, or while not even running at all and sitting in the driveway, the park lights will start to flash at very low intensity (can really only notice at night). About a minute later, I can hear a relay under the dash cycling a few times and eventually the horn will begin to blip (also at low intensity). About a dozen horn chirps will sound and then everything goes back to normal again.

I haven't been able to diagnose anything but that it seems to only do this in when it's cold outside (anywhere from +5 degrees C and lower).

Today, I went under the dash and removed the control module (which is when I learned what model I owned). The entire circuit board looks fine but for pin #8 of the 14 pin male connector. It appears discolored with a bit of carbon burning that also browned the white plastic of the circuit mount. (Pin #8 is for the white line - 10 AMP park light output).

Sorry for the novel - Does anyone have any ideas or should I just keep the module out, cover any exposed installation wires and leave it alone? BTW - since removing the module, all OEM systems seem to work fine.

That's not a novel--that's a lot of good information!

Everyone likes to say "bad ground" so much that people make fun of it, but really, if the unit loses its ground connection, it'll try to "find" some sort of a ground through the various other wires it's hooked up to, and strange things often happen like you're describing.

I'd first see where they grounded it, and maybe try redoing the ground connection even if it does look visually good.

If you have an Autozone near you, they have a display on the parts counter where they sell batteries for the remotes. There's a little tester there---use it to see if your remote is putting out signal or not.

I've only put in a few Ultra units, but I've seen that white wire turn brown before even on other brands. Probably the car's parking light circuit draws a little more current than the remote starter's connector is happy with, and it gets hot over time. But the worst that should happen would be that the parking light output would stop working.

Do you have any kind of install guide for this unit? Might be interesting to try to enter into programming mode. Don't go and change or reprogram anything, just see if you can get in.....that'll hopefully tell you if it's getting power and more or less working properly.