SERVICE BRAKES DO NOT WORK WHEN TRUCK IS BEING TOWED CONTINUED

TM9-2320-270-20-1

TROUBLESHOOTING - CONTINUED

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

68. SERVICE BRAKES DO NOT WORK WHEN TRUCK IS BEING TOWED CONTINUED.

Disconnect service hookup hose gladhand (1) color coded blue. Have

Step 7.

assistant apply trailer brakes in towing vehicle.

If there is air pressure at gladhand, release brakes and go to step 9.

Release brakes, go to towing vehicle and check service gladhand (2) and hose

Step 8.

(3) to trailer protection valve (4) for clogs, damage, or leaks by listening

for hissing or using soap solution and watching for bubbles (page 4-1).

a. If gladhand or hose are clogged, damaged or leaking, repair,

replace, or clean (page 4-838).

b. If gladhand or hose are not clogged, leaking or damaged, go

to SERVICE BRAKES DO NOT RESPOND WHEN APPLIED BY TRAILER

BRAKEHAND CONTROL (page 3-157).

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