Remote Car starter

Have a 95 with an aftermarket remote car starter and keyless entry. it has not worked for at least a year. I have had it in the car for at least 5 years. I do not know the brand but I can find out. The remote starter does not work and neither does the keyless entry. I put a new battery in the remote still nothing. I have heard of the hood switch corroding, haven't check that. I am wondering if I can pull the old one out and plug a new one in since it has all been wired. The place that installed it said the whole thing would have to be rewired. Common sense tells me that just want the money. If the wires are ran why would it need to be rewired? If I can get a similar model with same plug ends??? Any idea's

You are absolutely correct. If you can get the same model (Make sure the numbers match). It will be plug and play. I've done it. And yes, the shop wanted your money.
Before you invest in a new brain module for remote starter, unplug all the harnesses from the main box - wait 30 seconds - plug the harnesses back in and press a button on your remote - it may just have needed to recognize your remote - maybe not... some remote starts also have a sequence where you can erase the memory, if you have the installation booklet I would try that also.

Thanks;

The only other thing I would wounder is if my transmitter is acually working.