Circuit/System Testing

WARNING: This page is about a different car, the 2012 Buick Verano. 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 B10B ambient light/sunload sensor. Verify there are no electrical components connected to the vehicle to include the MDI or battery charger as applicable. It may take up to 10 minutes for all vehicle systems to power down.
Test for less than 5 Ω between the low reference circuit terminal 6 and ground.
- If 5 Ω or greater
1. Ignition OFF, disconnect the harness connector at the K33 HVAC control module.
2. 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 5 Ω
Ignition ON.
Test for 4.8-5.2 V between signal circuit terminal 4 and ground.
- If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K33 HVAC control module.
2. 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
3. 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
1. Ignition OFF, disconnect the harness connector at the K33 HVAC control module, ignition ON.
2. Test for less than 1 V between the 5 V reference 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 B10B ambient light sensor.
Verify DTC B0183 does not set while operating the vehicle under the Conditions for Running the DTC.
- If the DTC sets
  Replace the K33 HVAC control module
- If the DTC does not set
All OK