Isolate the blower vacuum switch. Measure
continuity between switch terminals. IF continuity
exist, replace switch (pg. 20). IF OK, go to 13B.
Verify blower operation
Test blower vacuum switch
Step 13A
57
Step 13B
“AC” Code stands for “Air Switch Closed”. The blower vacuum switch closed, when it
was expected to be open.
With the heater off (in “Stand By”), IF the blower
continues to run/operate, replace the ICB. IF not,
replace the blower vacuum switch (pg. 20).
13. Service LED ON: “AC” Code