Standard Procedure - Air Line Repair
All pressurized air suspension components contain high pressure air (up to 220 psig). Use extreme caution when inspecting for leaks. Wear safety goggles and adequate protective clothing when inspecting or servicing the air suspension system. A sudden release of air under this amount of pressure can cause possible serious or fatal injury.
Support the vehicle by supplemental means before performing any work on the air suspension system to prevent the vehicle from changing height. Before any given component is to be serviced it must be deflated. Servicing the air suspension system without supplemental support, or with pressure in the specific component, can cause possible serious or fatal injury.
Only two air line repairs may be performed on the entire air suspension system. If more than two repairs are made, excessive leakage may result in damage to the air compressor assembly.
A maximum of 7 mm (0.275 in.) is allowed between the ends of the air line inside the air suspension union after a repair. If after the damaged area of the air line is removed and the two ends of the air line are more than 7 mm (0.275 in.) apart, the air line must be replaced.
- Air lines can be repaired for a hole or puncture.
- Replace an entire line if cracked or crushed.
- Do not repair the air lines more than two times.
Place the vehicle in "Tire Jack Mode" before proceeding with any service procedure.
A brass air suspension union (1) comes fully assembled and is intended for use without any disassembly. There are plastic placeholders (2) inserted into the union (1) to keep out moisture/debris and to retain alignment of the line retainer inside the union. Do not remove the plastic placeholders (2) until ready to insert the line for repair. There are two O-rings inside and one O-ring on the threaded area of the nut on both ends of the union (1). Inside the union (1), between the body and the nut is a line retainer that locks the line in place when the line is pushed all the way into the union (1) and then pulled. The pulling action on the air line is what locks the line into place.
- Raise and support the vehicle. Refer to HOISTING, STANDARD PROCEDURE .
- With a scan tool, using the routines under the ASCM, perform the following:
- If the reservoir line is being repaired, Run the deflate reservoir to atmosphere routine.
- Access the air line as necessary so that approximately 305 mm (12 in.) of line is accessible around the damaged area.
- Clean the air line with mild rose water and thoroughly dry.NOTE:
Care must be taken when cutting the air line so that no ridge is created on the surface of the air line, and that the air line is not crushed into an oval shape or the air line adapter O-ring will not hold pressure.
- Using air line cutters, carefully cut the air line on each side (5, 4) of the damaged area (3) removing no more than 7 mm (0.275 in.).
- Remove one plastic placeholder (2) and insert the air line (3) fully into the union (1).
- Remove the remaining placeholder (2) and insert the air line (1) fully into the union (3).
- Grasp the air line on both sides of the union (3) and pull to seat the retainer and properly seal the union and lines.
- With a scan tool, using the routines under the Air Suspension Control Module (ASCM), perform the following:
- Fill Spring From Reservoir/Complete Fill (on the spring replaced) OR if the reservoir air line was replaced, command the vehicle to normal ride height.
- Run the Air Mass Calculation routine on the air suspension system.
- If necessary, add to the system or deflate to atmosphere using the ASCM routines, then repeat the Air Mass Calculation routine again until system responds with Air Mass OK (188 - 216 bar-liters).
- Enable the air suspension system.
- Remove the supports and lower the vehicle.
- Perform the ASCM Verification Test. Refer to STANDARD PROCEDURE - ASCM VERIFICATION TEST .