code 12 - start of code sequence
code 13 - Left rear time out
code 14 - Right front time out
Code 21 - Left front time out
code 22 - Right rear time out
code 23 - Loss of vehicle speed signal (Code 23 will set if the ignition
switch is cycled on and off 3 times without driving vehicle. the "service
ride control will turn off once the vehicle has been drivin if the system is
ok, but the code will remain as a history code and should be cleared to avoid
future misdiagnosis.
code 31 - Left front out of position
code 32 - Right front out of position
code 33 - Left rear out of position
code 34 - Right rear out of position
code 41 - Selective ride control switch short to voltage
code 42 - Selective ride control switch open contacts (Code 42 will set if
the selective ride control switch is not properly positioned in one of the
three detent positions.

HOW to READ THE TROUBLE CODES:

Selective ride trouble codes may be read with the vehicle stopped by
grounding terminal "C" of the assembly line diagnostic link (ALDL).

Observe the "service ride control" indicator with the ignition switch in the "run" position.
The trouble codes are comprised of two digits. A digit is read by
counting the number of flashes that occur within a half second of each other.

The second digit will appear about one second after the first digit has
gone. each code will repeat 3 times before the next code begins with a 3
second pause between codes. The entire trouble code sequence will reappear as long as terminal "C" is grounded. The trouble code display begins by showing code 12 three times, marking the beginning of the sequence.

If the diagnomode cannot be entered (no codes appear, not even code 12) refer directly to chart #5: "trouble codes cannot be read"

When the diagnosis is complete and any necessary repairs have been made, the trouble codes must be cleared to prevent further misdiagnosis.

To clear the system, ground pin "C" of the ALDL connector for two seconds and repeat the procedure twice for a total of three groundings.