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.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET2025TRAILBLAZER ACTIV, FWDREPAIR AND DIAGNOSIS (SINGLE PAGE)BODY & FRAMEBODY, CAB CONTROL SYSTEMSVEHICLE ACCESS SYSTEMDIAGNOSTIC INFORMATION AND PROCEDURESDTC B153F - LIFTGATE OBJECT SENSOR MALFUNCTIONCIRCUIT/SYSTEM TESTING
2025 Chevrolet Trailblazer ACTIV, FWD
Circuit/System Testing
2025 Chevrolet Trailblazer ACTIV, FWDSECTION Circuit/System Testing
- Ignition/Vehicle & All vehicle systems - Off
- Disconnect the electrical connector: B71R Liftgate Object Sensor - Right
- Verify a test lamp turns On between the test points: Low Reference terminal 2 & B+
- If the test lamp does not turn On
- Disconnect the electrical connector: K39 Liftgate Control Module
- Test for less than 2 ohms between the test points: Low Reference terminal 2 @ Component harness & Terminal 16 X1 @ Control module harness
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Replace the component: K39 Liftgate Control Module
- Go to next step: If the test lamp turns On
- Ignition - On / Vehicle - In Service Mode
- Disconnect the electrical connector: B71L Liftgate Object Sensor - Left
- Ignition - On / Vehicle - In Service Mode
- Test for 4.8 to 5.2 V between the test points: Signal circuit terminal 1 & Ground
- If less than 4.8 V
- Ignition/Vehicle - Off
- Disconnect the electrical connector: K39 Liftgate Control Module
- Test for infinite resistance between the test points: Signal circuit terminal 1 @ Component harness & Ground
- If less than infinite resistance - Repair the short to ground on the circuit.
- Go to next step: If infinite resistance
- Test for less than 2 ohms between the test points: Signal circuit terminal 1 @ Component harness & Terminal 8 X1 @ Control module harness
- If 2 ohms or greater - Repair the open/high resistance in the circuit.
- If less than 2 ohms - Replace the component: K39 Liftgate Control Module
- If greater than 5.2 V
- Ignition/Vehicle - Off
- Disconnect the electrical connector: K39 Liftgate Control Module
- Ignition - On / Vehicle - In Service Mode
- Test for less than 1 V between the test points: Signal circuit terminal 1 @ Component harness & Ground
- If 1 V or greater - Repair the short to voltage on the circuit.
- If less than 1 V - Replace the component: K39 Liftgate Control Module
- Go to next step: If between 4.8 and 5.2 V
- Test or replace the component: B71R Liftgate Object Sensor - Right or B71L Liftgate Object Sensor - Left
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.