For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Lumbar Support System Check? | -- | Go to Step 2 | Go to Lumbar Support System Check
2 | Is the symptom present for all of the seat lumbar switches? | -- | Go to Step 3 | Go to Step 8
3 | Test for an open or disconnected air line at one of the following components:

• | Seat air pump

• | Solenoid valve assembly

• | In the tubing between the seat air pump and the seat cushion air valve assembly

Are the air lines OK?

--

Go to Step 5

Go to Step 4

4 | Repair the air line problem. Is the repair complete? | -- | Go to Lumbar Support System Check | --
5 | Test the seat cushion air valve assemblies for leakage. Are the seat cushion air valve assemblies OK? | -- | Go to Step 6 | Go to Step 7
6 | Replace the seat air pump. Is the repair complete? | -- | Go to Lumbar Support System Check | --
7 | Replace the suspect seat cushion air valve assembly. Is the repair complete? | -- | Go to Lumbar Support System Check | --
8 | Test the associated air line for leaks between the seat cushion air valve assembly and the lumbar bladder. Are the air lines OK? | -- | Go to Step 9 | Go to Step 4
9 | Test the lumbar bladder for leaks. Is the bladder OK? | -- | Go to Step 5 | Go to Step 10
10 | Replace the lumbar bladder. Is the repair complete? | -- | Go to Lumbar Support System Check | --