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.
2007 Hummer H3 L5-3.7LFACTORY OEM SERVICE PROCEDURE
Oxygen Sensor: Locations
Engine Controls Component Views
Engine Controls Components
1 - Powertrain Control Module C1 (Body Harness)
2 - Powertrain Control Module
3 - Heated Oxygen Sensor (HO2S) 2
4 - Fuse Block - Underhood
5 - Engine Harness
6 - Heated Oxygen Sensor (HO2S) 1
7 - Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor
8 - Powertrain Control Module C3 (Engine Harness)
9 - Powertrain Control Module C2 (Engine Harness)
Engine Components - Right Side (L52)
1 - Manifold Absolute Pressure (MAP) Sensor
2 - Throttle Body
3 - Ignition Coil 3
4 - Ignition Coil 2
5 - Ignition Coil 1
6 - Camshaft Position (CMP) Actuator Solenoid - Bank 1 Exhaust
7 - Engine Oil Pressure (EOP) Switch
8 - Heated Oxygen Sensor (HO2S) 1
9 - Engine Coolant Temperature (ECT) Sensor
10 - Engine Coolant Temperature (ECT) Sensor Connector
11 - C101 Fuel Injector Harness to Engine Harness
12 - Ignition Coil 5
13 - Ignition Coil 4
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no 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.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
Comes to youSame-day available12-month warranty
Get a Free QuoteNo obligation. See pricing before you book.