2003 Honda Civic Maintenance Required Light on Continously

1. Tried standard option (turn ignition switch to OFF position.). This did not work. Took it to Jiffy lube, Midas during oil/service change. They could not fix it as well.

2. Took it to Honda Dealer. I was told it could be something to do with the Audiovox Key less car remote wiring as the maintenance light blinks when the car lock is getting reset. Is there a specific service technician that I should take it to fix this?

3. Car was manufactured in US and when I moved to Canada had to make some changes (@Canadian Tire) to have the Daytime running light to work.

There were no problems with after Daytime running light changes were done and the key-less entry wiring has been there since the car was bought. Maintenance required light came on and stayed on after 55,000 miles. Even though, I am told there are no issues in the maintenance light being on, I planning to sell the car and I feel it is better to fix this as the buyer might feel something wrong with the car with this light being on.

Also, I read in one of the similar questions in this forum, "If vehicle is equipped with daytime running lights and lights come on when ignition switch is turned to ON (II) position, daytime running lights must be disabled before indicator light can be reset.". I would like to know how to do this. Can I do this myself or do I need to take it to a service place?

Thanks very much in advance for your help.