P0537 - A/C Evaporator Temperature (ACET) Circuit Low Input

2004 Ford Econoline E150, Van Cargo, 4.6 WSECTION P0537 - A/C Evaporator Temperature (ACET) Circuit Low Input
P0537 - A/C EVAPORATOR TEMPERATURE (ACET) CIRCUIT LOW INPUT

Description:  Indicates the ACET signal input was less than the self-test minimum. The self-test minimum is 0.13 volts.
Possible Causes: 
  • ACET circuit short to ground or SIG RTN.
  • Damaged ACET sensor.
  • Damaged PCM.
Diagnostic Aids:  The PCM sources a low current 5 volts on the ACET circuit (this voltage can be measured with the sensor disconnected). As the A/C evaporator air temperature changes, the ACET circuit resistance to SIG RTN (ground) changes (which changes the voltage the PCM detects). When the ACET signal is detected below the self-test minimum, check for shorts to the SIG RTN or ground, which would pull the voltage low.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to DJ: Air Conditioner Evaporator Temperature (ACET) Sensor STEP 5 GO to DJ: Air Conditioner Evaporator Temperature (ACET) Sensor STEP 5 GO to DJ: Air Conditioner Evaporator Temperature (ACET) Sensor STEP 8
RENDER: 1.0x

NO RELATED

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