ineterior l.e.d.s, door pins and relays

it sounds like you have to hook up a relay to convert the polarity of the door trigger wire that should take care of the problem.

that didn't work.

Maybe this will work. The 74LS121 will produce an output pulse set by the values of R1 and C1. Pin 5 of the 74LS121 is a Schmitt trigger input. Once U2 detects a positive edge on pin 5 it will produce an output pulse of approximately 28 seconds then the output will go low and it will wait for another positive edge. The output pulse is used to turn on U3 which is a solid state relay driver designed especially for 12 volt relays and can be used with relays up to 500mA. U1 is a positive voltage regulator and is only there to provide a clean +5V to the 74LS121, if you already have a good +5V source in your car you don't need the 7805. Pin 5 of the 74LS121 is a TTL logic level input and only needs 4V to 5V to detect a high state. I added R2 assuming your input signal was +12V, you might have to play around with this value depending on the current draw of the input of the 74LS121. I have not built this curcuit so I have no idea if it will actually work for you purpose. I have never tried to use a +12 volt source for an input trigger to a 74LS121 so R2 is only a guess. DigiKey does sell all of these parts in single quantities.

Note: You can build a cuircuit based on this design but using a 74LS221 and a SC-74 case 318F if you need two inputs and two outputs with independent delay times. 74LS221 is a dual version of the 74121 and the Case 318F is a dual version of the 318. You would need an addition R1 R2 and C1. The output pulse time is roughly .7*R1*C1 2k-40k resistors and up to 1000uF caps may be used.