TEST OR INSPECTION
ALL LAMPS DO NOT LIGHT.
Check for burned out fuse in towing vehicle.
Replace fuse if burned out.
Check for loose receptacle ground leads.
b. Check for loose ground leads. Tighten if loose.
c. Replace access cover.
ONE OR MORE LAMPS (BUT NOT ALL) WILL NOT LIGHT
Check for burned out lamp.
Replace burned out lamp.
Check for corroded or dirty lamp sockets.
Clean lamp sockets.
Check for a broken circuit.
DIM OR FLICKERING LIGHTS.
Check for loose receptacle ground leads,
See Step 2 under Malfunction 1, ALL LMPS DO NOT LIGHT.
BRAKES WILL NOT RELEASE.
Check for broken brake shoe tension spring. Remove wheel and tire and brake drum to expose
If brake shoe tension spring is broken, replace the spring (para 4-33 or 4-34).
Test for leaking fail-safe chamber (para 4-39 or 4-40).
If fall-safe chamber is leaking, replace fail-safe chamber (para 4-39 or 440).
Charge air system from towing vehicle or outside source.
Check for leaks in secondary reservoir and connections if brakes still do not release.