Chassis C-codes

Dad has a '97 Town Car with air suspension. The “Check Air Suspension” light is coming on. I have replaced the compressor, but the light still comes on. I have an Actron code scanner that reads power train § codes. Are there any tools that can read the chassis © codes other than the $2K tools the dealers have.

The compressor is only one SMALL part of the Lincoln’s air suspension system. Now that you know you have a good one, you should next check for leaks. My guess is you will probably find at least one of the rear bags leaking. BTDT. There is also a “brain” for that system on the right side of the trunk behind the carpeting. Sniff it. If it smells burned, it is a candidate for replacement. About $300 from Lincoln, $50 from a good salvage yard.

The car’s air suspension is 11 years old now. This means that the rubber parts have probably degraded throughout.
Most leaks are at the solenoid O-rings or in the fold of the rubber bags where they fit over the metal sleeves.

This site here has some info on air suspension diagnostic and repair.

They provide some tips to for diagnosis without a scan tool and have a tool for free loaner use with a 500 dollar deposit and return of the tool within 10 days.

The problem you have is that by fixing one leak you’re opening up the possibility of another. In other words, fix a leaking left front bag only and the right one will go next week.
If you have a front strut off and compress it by hand you can see how bad dry rot is on those bags.

Another option is to convert the air springs to a “normal” suspension. I did this with my Lincoln Mark about a month ago with a kit from Arnott Industries.
About 400 bucks total for new coil over spring struts for the front and spring conversions for the rear. A couple of hours with basic tools and voila.
The car’s stance is fine and rides great with no annoying compressor hum, fear of being slammed to the ground, or irritating Check Air Ride beeping. (Killing the messages is simple to do also by unplugging the gray connector at the air ride module.)
I think the Town Car conversion is even cheaper than the Mark.
Just an idea if you want to consider it.