P1436 Buick A/C Evaporator Air Temperature Circuit Low
Possible causes
Tech description
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.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1436 Buick Description
Indicates the ACET signal input was less than the self-test minimum. The self-test minimum is 0.13 volts.
Buick Vehicle:Buick Regal – ?Buick Riviera – ?Buick LaCrosse – ?David Dunbar Buick – Buick Century – Buick LaCrosse – Buick LeSabre – Buick Lucerne – Buick Park Avenue – Buick Regal – Buick Verano – Buick Enclave – Buick Encore – Buick Rainier – Buick Rendezvous – Buick Terraza – Buick Riviera