Trane S8V2A040M3PC Installation, Operation And Maintenance Manual page 77

DEFINITION:
This fault is generated when the Return Sta c
pressure transducer (BAYFURNPTKT accessory)
is out of bounds or has been enabled and the
wiring harness has not been connected to the IFC.
NOTE:
This error does not affect opera on of the furnace.
Important:
The Link mobile app must be used to enable or
disable the pressure transducer. Disabled is the
factory default.
DEFINITION:
This fault is generated when the Return temperature
sensor is Open / Shorted or when the sensor has been
enabled but not installed/plugged in.
The sensor is part of the blower wiring harness.
NOTE:
This error does not affect opera on of the
furnace. It can be cleared by disabling the Return
Temperature using the mobile diagnos cs app or by
using the Menu / Op on bu ons. (24VAC mode only)
BK/38 4
C
3 RX
BLOWER
2 TX
GND
MOTOR
V J1
1
J2
GY/57
THERMISTOR
120v 60 Hz. 1 PH
POWER SUPPLY PER LOCAL CODE
1 2 3 4 5 6 7 8 9 10 11 12
1 2 3 4 5 6 7 8 9 10 11 12
JUNCTION BOX
S8V2-SVX001-1A-EN
Disbale the return
sta c kit from the
Link mobile app
5 BK/39
L1
N 4 WH/40
3 GR/41
2 BLOWER
HOUSING
YL/42
1
GND
GY/56
H N
GND
X X X X
E26 Fault Code
Is BAYFURNPTKT
NO
installed?
Verify source voltage is 5vdc form
the IFC and the voltage output
corresponds to the pressure measured
E27 Fault Code
Measure the DC voltage between GY/63
and GY/64 connecter E21(RET_T) on the IFC
Refer to the Thermistor table
Unplug connector E21 and verify ~3.2 Vdc between
pins Replace IFC if voltage is less than 3Vdc
Turn Power OFF to the furnace
Remove the 12 pin blower harness and measure
the resistance between GY/56 and GY/57
Refer to the Thermistor table
If resistance reading is Open or Shorted,
replace blower wiring harness
T T r r o o u u b b l l e e s s h h o o o o t t i i n n g g
77