Manual Temperature Control

B113E - Rear Mode Request High

For a complete wiring diagram, refer to.

Theory of Operation

When the rear A/C heater control is used to adjust the rear mode door actuator, the A/C heater control receives a rear mode request signal via the rear mode door driver circuit. The A/C heater control drives the rear mode door actuator via the rear mode door driver circuit and the common door driver circuit.

• When Monitored: With the ignition on.

• Set Condition: If the A/C heater control detects a short to voltage on the rear mode door driver circuit when the rear A/C heater control is used to adjust the rear mode door actuator.






• The DTC must be active for the results of this test to be valid. Do not perform this test if the DTC is stored. Refer to => Non-DTC Based Diagnostics for stored DTC test procedures.

Test Step 1 - Check for an Active DTC with Rear A/C Heater Control Disconnected

• Turn the ignition OFF.

• Disconnect the rear A/C heater control 8 way harness connector.

• Turn the ignition ON.

• With the scan tool, erase HVAC DTCs.

• Turn the ignition OFF, wait 10 seconds, and then turn the ignition ON.

• With the scan tool, read HVAC DTCs.

Does the scan tool display this DTC as active?

Yes

• Go to Test Step 2 => [ Test Step 2 - Check Rear Mode Door Driver Circuit for a Short to
Voltage ]

No

• Replace the rear A/C heater control.

• Perform the HVAC Verification Test. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

Test Step 2 - Check Rear Mode Door Driver Circuit for a Short to Voltage

• Turn the ignition ON.

• Measure the voltage between ground and the rear mode door driver circuit in the rear A/C heater control 8 way harness connector.

Is the voltage less than 0.2 volts?

Yes

• Go to Test Step 3 => [ Test Step 3 - Check Rear Mode Door Driver Circuit for a Short to
Other Rear A/C Heater Control Circuits ]

No

• Repair the rear mode door driver circuit for a short to voltage.

• Perform the HVAC Verification Test. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

Test Step 3 - Check Rear Mode Door Driver Circuit for a Short to Other Rear A/C Heater Control Circuits

• Turn the ignition OFF.

• Measure the resistance between the rear mode door driver circuit and the rear blower feed sense circuit, the HVAC MUX return circuit, the rear blend sense supply circuit, the panel lamps driver circuit, the rear blower on indicator driver circuit, and the rear A/C temp control circuit in the rear A/C heater control harness connector.

Is the resistance less than 100 ohms between any of the circuits?

Yes

• Repair the circuits with a resistance less than 100 ohms for a short together.

• Perform the HVAC Verification Test. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

No

• Replace the front A/C heater control.

• Perform the HVAC Verification Test. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test