I had my 1999 ford expedition rear air suspension repaired
they replaced the rear air shocks & now the check suspension light is on and the air pump isn't coming on
do you have to reset the computer
if so how
The fact that the air suspension light is on means that there are stored trouble codes in the Vehicle Dynamics (VDM) module. The dealer will be able to retrieve these codes and see what type of fault is indicated. It is possible that the compressor is failing because it was overworked when there was a leak in the system. But without doing some diagnosis, that is just speculation. So, make sure the air suspension switch is on, check the air lines and wires for obvious faults, and have the dealer check it for codes. I would push for a free checking of the codes at this point, since it is basically a re-check on an ongoing problem, but it is conceivable that a new and unrelated problem has developed coincidentally, and it may require some more diagnostic time to figure out.
There are also 2 front height sensors and one rear height sensor. These sensors extend and retract, creating voltage signals based on height. They each have an electrical connector.