Circuit/System Testing
WARNING: This page is about a different car, the 2015 Chevrolet Trax and 2015 Buick Encore. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B39 A/C Evaporator Temperature Sensor. It may take up to 10 min for all vehicle systems to power down.
- Test for less than 10 Ω between the low reference circuit terminal B and ground.
- If 10 Ω or greater
- Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module.
- Test for less than 2 Ω in the low reference circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K33 HVAC Control Module.
- If less than 10 Ω
- Test for 4.8-5.2 V between the signal circuit terminal A and ground.
- If less than 4.8 V
- Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module.
- Test for infinite resistance between the signal circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K33 HVAC Control Module.
- If greater than 5.2 V
- Ignition OFF, disconnect the harness connector at the K33 HVAC Control Module, ignition ON.
- Test for less than 1 V between the signal circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K33 HVAC Control Module.
- If between 4.8-5.2 V
- Test or replace the B39 A/C Evaporator Temperature Sensor.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
- Verify the DTC does not set.
- If the DTC sets
Replace the K33 HVAC Control Module.
- If the DTC does not set
- If the DTC sets
- All OK
NOTE:
The scan tool must be disconnected from the vehicle before performing the next test.