SPRING BRAKES WILL NOT RELEASE.

TM 9-2320-279-20-1

Troubleshooting Malfunctions (Cent)

2-9.

Malfunction

Test or Inspection

Corrective Action

DUAL AIR BRAKE SYSTEM

7. SPRING BRAKES WILL NOT RELEASE.

Step 1. Check for binding slack adjuster. Lubricate slack adjuster (LO 9-2320-279-12).

Step 2. Check air lines and spring brake components for leaks or damage.

If lines or spring brake components are leaking or damaged, repair lines or replace

components (go to Alphabetical Index to find component replacement procedures).

Step 3. Release parking brakes. Loosen spring brake air line on brake chamber.

If air comes out of hose, replace brake chamber (para 11-8).

LINE NO. 622

SPRING BRAKE

RELAY VALVE

LINE NO. 620

Step 4. Release spring brakes. Loosen line No. 620 at spring brake relay valve.

If air does not come out of line No. 620, replace No. 1 air manifold (para 11-25).

Step 5. Loosen line No. 622 at spring brake relay valve.

If air comes out of line No. 622, replace spring brake relay valve (para 11-17).