2008 Lucerne suspension code

[buickkyle1209]

I have recently purchased a 2008 Buick Lucerne with 129,000 miles on it. When I bought it, the dealer said it had been sitting for a good 6 months and when I test drove it, the suspension was shot. I took it and got some conventional shocks put on it (I was not gonna drop 1200 for the stock ones) and they never turned off the air suspension. Whenever I turn it on, after about five seconds of running a pump runs in the rear of my vehicle and a warning pops up saying "service suspension" and it limits my speed and that is annoying because I live in South Dakota where the speed limit is 80 and it is limited to 82. It's annoying when trying to pass someone going like 2 under. Is there a way to get rid of that code without a code reader and taking it back?

 

[2007LucerneCXL]

Here's the Monroe shock conversion from air to regular shocks instructions which may help.