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Servicing should only be performed by a Qualified Service Technician
STEP 4: TEST FOR 24VAC BETWEEN BLACK AND YELLOW ON DAMPER PC
BOARD
IF
THEN
24VAC is present
•
This is correct - Continue to Step 5.
24VAC is not present.
•
Check Service Switch position.
•
Check the harness plug connections.
•
Check that cam on shaft rotates with shaft.
•
Replace the damper assembly.
STEP 5: WIRE HARNESS TEST
CONDITION:
•
Damper Open, no 24VAC to module "24VAC" terminal.
Test for 24 VAC between terminal 24V on the IID module, and 24V GND.
IF
THEN
24VAC is present
•
This is correct - Continue to Step 5.
24VAC is not present.
•
Check Service Switch position.
•
Check the harness plug connections.
•
Check that cam on shaft rotates with shaft.
•
Replace the damper assembly.
Note:
This test may be easier to conduct by removing the red wire from the IID terminal. Test for 24 VAC
between the red wire and ground. Reconnect the red wire to the 24V terminal after the test.
