Carrier SERIES 131 58PAV - Manual (Page 10)

Close door switch and go to start. Is circuit breaker closed?
Is red LED status light on? Is red LED status light blinking rapidly without a pause?
Is door switch closed? Is there 115v going to switch?
Replace control board.
Replace door switch.
Is red LED status light blinking ON/OFF slowly with a combination of short and long flashes?
Check for correct line voltage polarity. If units are twinned, check for proper low-voltage (24v) transformer phasing. Check for previous fault by momentarily shorting the TEST terminal and the "C" terminal until the LED goes out. LED will flash the status code of any previous fault or the code 11 (ONE SHORT AND ONE LONG FLASH) if no previous fault. After the control repeats the code 3 times, it will sequentially operate inducer motor, HSI, blower motor relay heat speed, and cool speed for approximately 10 - 15 sec, then go off.
Determine status code. The status code is a 2 digit number with the first digit determined by the number of short flashes and the second digit by the number of long flashes. Once status code is determined, the control will go through a brief component test sequence by operating inducer motor, HSI, blower motor relay heat speed, and cool speed for approximately 10-15 sec, then go off.
Was there a previous fault code other than No. 11?
Run system through a heating or cooling cycle to check operation. Status codes are erased after 48 hrs or whenever power (115v or 24v) is interrupted.
Go to section with status code determined.
Is there 115v at L1 and L2?
NO
NO NO
NO NO
YES
YES YES
YES YES
NO
NO YES YES
YES
START
Is there 24v at SEC-1 and SEC-2?
NO
TROUBLESHOOTING GUIDE
Replace transformer.
Close circuit breaker and go back to start.
NO
Check for continuity in wire from circuit breaker to furnace.
YES
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