GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2001 🢒 Sonoma Pickup - 2WD 🢒 Suspension 🢒 Automatic Level Control 🢒 Air Compressor Leak Test

Step

Action

Value(s)

Yes

No

DEFINITION: The objective of this check is to identify and repair potential leaks and/or blockages in the automatic level control system air path.

1
  1. Disconnect the electrical connection to the automatic level control air compressor and the automatic level control solenoid valve.
  2. Disconnect the air line from the automatic level control air dryer and connect the air line to the J 22124-B on the side opposite the toggle valve. Close the toggle valve (down position).
  3. Apply service air pressure to J 22124-B service valve until the gauge reads 550 kPa (80 psi).
  4. Monitor the J 22124-B gauge pressure for 1 minute.

Do the air sleeves on both shocks inflate and lift the vehicle and does the system maintain pressure?

--

Go to Step 2

Go to Step 8

2
  1. Slowly release pressure from the system using the J 22124-B service valve.
  2. Connect the fused jumpers to the automatic level control solenoid valve, terminal A to ground and terminal B to B+.
  3. Apply service air pressure to the J 22124-B service valve until the gauge reads 550 kPa (80 psi).

Does the air sleeve on either shock inflate?

--

Go to Step 3

Go to Step 4

3
  1. Replace the automatic level control solenoid valve solenoid. Refer to Automatic Level Control Solenoid Valve Replacement .
  2. Perform the automatic level control system operation check in order to verify the repair. Refer to Automatic Level Control System Operation Check .

Is the repair complete?

--

Go to Step 4

--

4
  1. Disconnect the small air line connector from the automatic level control solenoid valve.
  2. Monitor the J 22124-B gauge pressure for 1 minute.

Does the pressure leak down within 1 minute?

--

Go to Step 3

Go to Step 5

5

Depress the core of the automatic level control solenoid inflator fill valve.

Is the pressurized air available at the automatic level control solenoid inflator fill valve?

--

Go to Step 6

Go to Step 3

6

Inspect the automatic level control air compressor filter hose for leaks, kinks or blockages.

Did you find any problems?

--

Go to Step 7

System OK

7
  1. Replace the automatic level control air compressor filter hose. Refer to Automatic Level Control Air Filter Hose Replacement .
  2. Perform the automatic level control system operation check in order to verify the repair. Refer to Automatic Level Control System Operation Check .

Is the repair complete?

--

Go to Step 8

--

8
  1. Check the following items for poor air line connections:
    2. • The shock absorber
    • The crossover air line tee
    • The automatic level control solenoid valve
    • The J 22124-B
    • Check for kinks in the air line and proceed if OK.
  2. Slowly release pressure from the system using the J 22124-B service valve. Disconnect the J 22124-B .
  3. Disconnect the air lines at both shock absorbers.
  4. Connect the right hand shock absorber to the J 22124-B on the side opposite the toggle valve. Close the toggle valve (down position).
  5. Apply service air to the J 22124-B service valve until the gauge reads 550 kPa (80 psi).
  6. Monitor the J 22124-B gauge pressure for 1 minute.
  7. Repeat the procedure for the left hand shock absorber.

Does either shock absorber not inflate or leak down within 1 minute?

--

Go to Step 9

Go to Step 10

9
  1. Replace the shock absorber. Refer to Shock Absorber Replacement in Rear Suspension.
  2. Perform the automatic level control system operation check in order to verify the repair. Refer to Automatic Level Control System Operation Check .

Is the repair complete?

--

Go to Step 10

--

10
  1. Slowly release pressure from the system using the J 22124-B . Disconnect the J 22124-B .
  2. Connect the air line to the shock absorbers.
  3. Disconnect the body harness air line from the crossover air line tee.
  4. Connect the crossover air line tee to the J 22124-B on the side opposite the toggle valve. Close the toggle valve (down position).
  5. Apply service air to the J 22124-B service valve until the gauge reads 550 kPa (80 psi).
  6. Monitor the J 22124-B gauge pressure for 1 minute.

Does either shock absorber not inflate or does the system leak down within 1 minute?

--

Go to Step 11

Go to Step 12

11
  1. Replace the crossover air line assembly. Refer to Air Tube Replacement .
  2. Perform the automatic level control system operation check in order to verify the repair. Refer to Automatic Level Control System Operation Check .

Is the repair complete?

--

Go to Step 12

--

12
  1. Slowly release pressure from the system using the J 22124-B service valve. Disconnect the J 22124-B .
  2. Connect the body harness air line to the crossover air line tee.
  3. Disconnect the small air line connector from the inflator solenoid.
  4. Connect the small air line connector to the J 22124-B on the side opposite the toggle valve. Close the toggle valve (down position).
  5. Apply service air to the J 22124-B service valve until the gauge reads 550 kPa (80 psi).
  6. Monitor the J 22124-B gauge pressure for 1 minute.

Does either shock absorber not inflate or does the system leak down within 1 minute?

--

Go to Step 13

Go to Step 14

13
  1. Replace the jumper air line from the solenoid to the crossover air line tee. Refer to Air Tube Replacement .
  2. Perform the automatic level control system operation check to verify the repair. Refer to Automatic Level Control System Operation Check .

Is the repair complete?

--

Go to Step 14

--

14
  1. Slowly release pressure from the system using the J 22124-B service valve. Disconnect the J 22124-B .
  2. Disconnect the small air line connector from the inflator solenoid.
  3. Disconnect the large air line connector from the inflator solenoid.
  4. Connect the large fitting on the inflator solenoid to the J 22124-B on the side opposite the toggle valve. Close the toggle valve (down position).
  5. Apply service air to the J 22124-B service valve until the gauge reads 550 kPa (80 psi).

Does either shock absorber not inflate or does the system leak down within 1 minute?

--

Go to Step 3

Go to Step 15

15
  1. Replace the jumper air line from the automatic level control solenoid valve to the automatic level control air dryer. Refer to Air Tube Replacement .
  2. Perform the automatic level control system operation check in order to verify the repair. Refer to Automatic Level Control System Operation Check .

Is the repair complete?

--

System OK

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