Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit/System Testing
2019 Chevrolet Trax Premier, AWDSECTION Circuit/System Testing
WARNING: This page is about a different car, the 2018 Chevrolet Trax and 2018 Buick Encore. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition/Vehicle & All vehicle systems - Off
- Disconnect the electrical connector: B9 Ambient Air Temperature Sensor
- Test for less than 10 ohms between the test points: Low Reference circuit terminal B (or 2) & Ground
- If 10 ohms or greater
- Disconnect the electrical connector: K20 Engine Control Module
- Test for less than 2 ohms between the test points: Low Reference circuit terminal B (or 2)@Component harness & The other end of the circuit
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Replace the component: K20 Engine Control Module
- Go to next step: If less than 10 ohms
- Ignition - On / Vehicle - In Service Mode
- Verify the scan tool parameter: Ambient Air Temperature = Less than -34°C (-30°F)
- If -34°C (-30°F) or warmer
- Ignition/Vehicle - Off
- Disconnect the electrical connector: K20 Engine Control Module
- Test for infinite resistance between the test points: Signal circuit terminal A (or 1)@Component harness & Ground
- If less than infinite resistance - Repair the short to ground on the circuit.
- If infinite resistance - Replace the component: K20 Engine Control Module
- Go to next step: If -35°C (-31°F) or colder
- Connect a 3 A fused jumper wire between the test points: Signal circuit terminal A(or1) & Low Reference circuit terminal B(or2)
- Verify the scan tool parameter: Ambient Air Temperature = Greater than 143°C (290°F)
- If 143°C (290°F) or colder
- Ignition/Vehicle - Off & Remove - Jumper wire(s)
- Disconnect the electrical connector: K20 Engine Control Module
- Ignition - On / Vehicle - In Service Mode
- Test for less than 1 V between the test points: Signal circuit@Component harness & Ground
- If 1 V or greater - Repair the short to voltage on the circuit.
- Go to next step: If less than 1 V
- Ignition/Vehicle - Off
- Test for less than 2 ohms between the test points: Signal circuit@Component harness & The other end of the circuit
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Replace the component: K20 Engine Control Module
- Go to next step: If 144°C (291°F) or warmer
- Connect the component: B9 Ambient Air Temperature Sensor
- Operate the vehicle within the Conditions for Running the DTC.
- Verify the DTC does not set.
- If the DTC sets
Replace the component: B9 Ambient Air Temperature Sensor
- Go to next step: If the DTC is not set
- If the DTC sets
- All OK.
NOTE:
It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.