TM 9-2320-272-24-1
Table 2-7. CTIS Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
4. SYSTEM REPEATEDLY RESUMES CYCLING 30 SECONDS AFTER MODE LIGHT STOPS FLASHING
NOTE
The ECU is programmed to check tire pressures 30 seconds after
completing a pressure changing sequence. The ECU does this to
verify that all wheel valves are properly closed before making
pressure checks at fifteen minute intervals. If the ECU repeatedly
checks pressure 30 seconds after a mode light stops flashing, it is
indicative of one or more tires losing air.
Test 1. Determine if tire(s) is losing air.
Shut off engine (TM 9-2320-272-10) and listen for air leaks.
Refer to malfunction 2, test 1, steps 1 and 2.
Test 2. Determine if wheel valve(s) is closing correctly.
Step 1. If individual tire(s) is low and leaks cannot be traced to faulty air lines, determine if
wheel valve(s) is leaking.
Refer to malfunction 2, test 1, steps 3 and 4.
Step 2. If both tires on same axle are low, check for restricted air line(s) to quick exhaust valve.
Refer to malfunction 1, test 1, step 1.
Step 3. Check quick exhaust valve for restriction.
Refer to malfunction 1, test 4, steps 1 and 2.
Step 4. Run engine at 1000 rpm and select HWY mode. Upon reaching air pressure indicated by
steady mode light reading, shut off engine. Wait for audible air flow from pneumatic
controller to stop.
Step 5. Disconnect and plug air line connected to top of each quick exhaust valve. Check shut-off
function of pneumatic controller by repeating step 4. If shut-off function does not occur,
replace or repair pneumatic controller (pare. 3-454).
Step 6. Connect air lines to top of each quick exhaust valve.
END OF TESTING!
5. SYSTEM SHUTS OFF WRING INFLATION, SINGLE MODE LIGHT CONTINUES TO FLASH
NOTE
If CTIS continuously shuts off air to wheel valves during air
compressor recovery, perform the following teat.
Check for air line leaks.
Inspect air lines from pneumatic controller and quick exhaust valves for leaks, cracks, damage, or
restrictions.
Refer to malfunction 1, test 1, step 1.
END OF TESTING!
6. SYSTEM FAILS TO DEFLATE, PARTIALLY DEFLATES, OR TIRE PRESSURES ARE IMBALANCED
NOTE
During deflation, all tires respond independently, Generally,
failure of the entire system to deflate indicates a control problem.
Failure of an individual tire to deflate indicates a problem at the
wheel.
Test 1. Determine control pressure during deflation.
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