Hello.
I am wondering if the remote will need a reprogram when the car battery gets disconnected for a long period of time.
I ask this because on other cars the remote fob loses the programming and you need to do it again either if you change the battery on the car or on the fob itself.

I am planning to leave the battery disconnected for about 4 to 6 months And during that time the remote fob could also lose its battery power.

 

FAQ, scroll to the lower portion:
https://www.clublexus.com/forums/ls-...questions.html

 

Thank you. I couldn't find what happens to the programmed keys if the battery on the car is disconnected for a long period of time.
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then learn how to do a search on the forum... it has been asked before.

 

I did made a search and got two opposite results.
One says it works fine after disconnecting everyday and the other says it doesn't after the battery died
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I had a battery die and did not find out till two weeks later. New battery and other than doing the radio and time adjustments, no other issues. YMMV and so long as you have a master key, programming is easy.

 

I am planning to leave the battery disconnected for about 4 to 6 months
By "Master key" you mean a working remote fob?

 

No, the black master key, not the gray valet key. The master key is required to begin any programming sequence for the fob. Without it, any fobs cannot be registered/programmed to the car. This is where I will say to have spares of that master key available for this reason.

An alternate suggestion would be to use a battery maintainer to keep the battery voltage maintained. Battery's will self discharge so that 4-6 months may be enough time span to have it discharge and depending on age may or may an issue on return. The other suggestion would be to have some trusted family/friend drive the car up to operating temperature twice a month.

 

I can only ask a friend to start the engine. Is that enough to keep the battery charge level if the engine runs for about 10 minutes once a week?

 

Keeping the fluids circulating is optimal but not usually convenient. If the power to the house/garage is not going to be shut off the battery maintainer is my suggestion here. 10 minutes may be sufficient to keep the battery going. The tires will flat spot from sitting so that is why driving the car will prevent this. Battery maintainers vary by features, similar to these on Amazon:

My buddy likes this one:

There is more to this than just disconnecting the battery for this short term storage. This discussion has some additional insights: Varies among some though this has the basics to prep the car.
https://mechanics.stackexchange.com/...out-driving-it