Invalid Conditions For Cooldown Test, EVAP Temperature Too Low

NOTE: After making any repairs, perform BODY VERIFICATION TEST under VERIFICATION TESTS.

Start engine. Turn A/C compressor off. Manually place ATC control panel mode selector to bi-level/mix position. Move temperature lever to full hot position. Place blower motor to highest setting. Operate engine at raised idle for about 5 minutes, to ensure evaporator temperature is greater than 55°F (12.7°C). Actuate A/C cool down test. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in HVAC. If scan tool display reads COOL DOWN TEST TOO COLD TO START, go to next step. If no such message is displayed, follow scan tool screen prompts and continue with A/C cool down test. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in HVAC.
Turn engine off. Turn ignition switch to ON position. Using scan tool, check for ATC DTC/fault messages. If no additional ATC DTC/fault messages are present, go to next step. If any additional ATC DTC/fault messages are present, go to appropriate procedure for DTC/fault message present. See DIAGNOSTIC TROUBLE CODE IDENTIFICATION table.
Using scan tool, check Powertrain Control Module (PCM) for DTC/fault messages. If no PCM DTC/fault messages are present, go to next step. If any additional PCM DTC/fault message is present, go to appropriate procedure for DTC/fault message. See SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. After repair of PCM concern, use scan tool to erase DTC/fault messages. Cycle ignition switch. Perform A/C cool down test. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in HVAC.
Turn ignition switch to OFF position. Disconnect evaporator temperature sensor 2-pin harness connector. Turn ignition switch to ON position. Using scan tool, select SENSOR DISPLAY, then read evaporator temperature sensor value. If value on scan tool reads less than 4.9 volts, go to step 6. If reading is 4.9 volts or more, go to next step.
Turn ignition switch to OFF position. Connect jumper wire between evaporator temperature sensor 2-pin harness connector terminals. Turn ignition switch to ON position. Using scan tool, select SENSOR DISPLAY, then read evaporator temperature sensor value. If value reads more than zero volts, go to next step. If reading is zero volts, replace evaporator temperature sensor. After repair, perform A/C cool down test. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in HVAC.
NOTE: When backprobing connectors, ensure DVOM test leads are in good contact with specified connector terminal. Ensure DVOM test leads are connected for positive polarity reading. If reading is not as specified, reverse test leads and retest.
Using DVOM, backprobe for voltage between evaporator temperature sensor 2-pin harness connector Dark Blue/Dark Green wire terminal, and ATC module connector C2 terminal No. 2 (Dark Blue/Dark Green wire). If reading is less than .10 volt, go to next step. If reading is .10 volt or more, repair high resistance in Dark Blue/Dark Green wire between ATC connector C2 terminal No. 2, in-line connector C202 terminal No. 13, and evaporator temperature sensor connector. See Figure, Figure and Figure . After repair, perform A/C cool down test. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in HVAC.
Using DVOM, backprobe for voltage in Dark Blue/Light Green wire between evaporator temperature sensor 2-pin harness connector, and ATC module connector C2 terminal No. 1. If reading is less than .10 volt, replace ATC module. Calibrate ATC module and actuators. See HVAC CONTROL CALIBRATION under PROGRAMMING. If reading is .10 volt or more, repair high resistance in Dark Blue/Light Green wire between ATC connector C2 terminal No. 1, in-line connector C202 terminal No. 12, and evaporator temperature sensor connector. See Figure, Figure and Figure . After any repair, perform A/C cool down test. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in HVAC.