DTC 2: Mode Actuator Did Not Reach Panel Position

When the HVAC control module calibrates the mode door actuator, it first moves the mode door actuator toward the defrost position then toward panel position. In the panel position, circuit C37 at HVAC control module 21-pin connector terminal No. 6 (Yellow wire) should have a value of 3.8-4.5 volts. When the mode door actuator does not reach the panel position and circuit C37 voltage is less than 3 volts, DTC 2 sets.

1. Turn ignition switch to OFF position. Disconnect mode door actuator connector 5-pin connector. Turn ignition switch to ON position. Scan tool will display DTC 2 when circuit C37 voltage is less than 3 volts.
2. Using DVOM, measure voltage between mode door actuator connector terminals No. 1 (Dark Green/Yellow wire) and No. 5 (Dark Blue/White wire). See Figure . If reading is not 11-13 volts, check for an open or short to ground in mode door driver circuits. Check Dark Green/Yellow wire between HVAC connector C1 terminal No. 18 and mode door actuator connector. Check Dark Blue/White wire between HVAC connector C1 terminal No. 12 and mode door actuator connector. See Figure and Figure . If reading is 11-13 volts, go to next step.
3. Measure voltage between mode door actuator connector terminals No. 2 (Dark Blue/Gray wire) and No. 4 (Pink/Dark Blue wire). See Figure . If voltage is less than 4 volts, check for an open or short to ground in 5-volt reference circuit from mode door actuator connector to HVAC control module connector C1 terminal No. 9 (Pink/Dark Blue wire). See Figure . If reading is 4 volts or more, go to next step.
4. Measure voltage between mode door actuator connector terminals No. 3 (Yellow wire) and No. 4 (Pink/Dark Blue wire). See Figure . If voltage is less than 4.5 volts, check for an open or short to ground in actuator feedback signal circuit from mode door actuator connector to HVAC control module connector C1 terminal No. 6 (Yellow wire). See Figure . If reading is 4.5 volts or more, go to next step.
5. Remove mode door actuator. Ensure mode actuator cam gear pins are in correct track on mode door actuator cam and defrost door gear, panel door gear and heat door gears are properly aligned and do not bind during operation. See Figure and Figure . If cam, pins and gears are okay, go to next step. If not okay, repair or replace mode actuator, mode door gears, gear pins and mode actuator cam as necessary. Go to  7 .
6. Ensure mode door operates smoothly and can travel through its full range of motion. Check mode door for binding. Repair binding as necessary. If mode door is okay, replace mode door actuator. Go to next step.
7. After repairs are complete, perform calibration test and cool-down test. See ACTUATOR CALIBRATION, DIAGNOSTICS & COOL-DOWN TESTS  under PROGRAMMING. Ensure all DTCs have been cleared from HVAC control module.