SEVERE PRESSURE DROP WHEN BRAKE PEDAL IS APPLIED OVER 25 PSI (172 KPA). cont'd

TM9-2320-270-20-1

TROUBLESHOOTING - CONTINUED

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

Step 7.

While assistant applies brake pedal, check rear axle relay valve (4) for damage

or leaks by listening for hissing or using soap solution and watching for

If relay valve is damaged or leaking, release brakes and replace valve

(page 4-785).

Step 8.

While assistant applies brake pedal, check pilot hose no. 660 (5) between spring

brake relay valve (2) and rear axle relay valve (4) for damage or leaks by listen-

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

If hose is leaking, release brakes and repair or replace hose

(page 4-609).

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