P1536

Circuit Description
This diagnostic test monitors the ECT sensor for a high engine temperature condition. It a high engine temperature condition exists it will either disable Air Conditioning (A/C) compressor it engaged or not allow compressor operation if requested during the high engine temperature condition. After the diagnostic test fails and is set current it uses a lower temperature cutoff point to ensure that the A/C system won't be a load on the cooling system during conditions of high engine temperature.

Conditions for Running the DTC
DTCs P0117, P0118 not set.

Conditions for Setting the DTC
^ A/C Compressor operation requested by HVAC controller.
^ Coolant temperature is greater than 125°C (257°F).
^ DTC P1536 not current.
OR
^ A/C Compressor operation requested or not requested by HVAC controller.
^ Coolant temperature greater than 1 20°C (248°F).
^ DTC P1536 current.

Action Taken When the DTC Sets
^ A/C compressor is disengaged.
^ The Malfunction Indicator Lamp (MIL) will not illuminate.
^ The PCM will command a message to be displayed.
^ The PCM may record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records.

Conditions for Clearing the Message/DTC
^ The PCM will turn the message OFF after one run and pass of the diagnostic test.
^ A History DTC will clear after forty consecutive warm-up cycles with no failures of any non-emission related diagnostic test.
^ A Last Test Failed (current) DTC will clear when the diagnostic runs and does not fail.
^ Use a scan tool to clear DTCs.
^ Interrupting PCM battery voltage may or may not clear DTCs. This practice is not recommended.

Diagnostic Aids
This DTC is associated with an overheating/low coolant level condition.