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.
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HOMESERVICE MANUALSCHEVROLET2001CHEVY EXPRESS G2500, VAN CARGO EXTENDED, 5.7 R, L31/KL8REPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 248 (ENGINE CONTROLS - SELF-DIAGNOSTICS)DIAGNOSTIC TESTSDTC P0030: HO2S HEATER CONTROL CIRCUIT (SENSOR 1)TEST DESCRIPTION
2001 Chevrolet Chevy Express G2500, Van Cargo Extended, 5.7 R, L31/KL8
Test Description
2001 Chevrolet Chevy Express G2500, Van Cargo Extended, 5.7 R, L31/KL8SECTION Test Description
WARNING: This page is about a different car, the 2003 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step number in the diagnostic procedures.
- 3
This step determines if the PCM is supplying voltage from the high side driver through the HO2S bank 1 sensor 1 heater high control circuit. - 4
This step determines if ignition 1 voltage is being supplied from the underhood fuse block. The battery voltage in this step indicates a functional low control circuit for both front sensors. - 7
The bank 1 sensor 1 and the bank 2 sensor 1 low control circuits are internally connected within the PCM. A short to ground between the HO2S bank 2 sensor 1 low control circuit and the PCM will set this DTC.
RENDER: 1.0x
NO RELATED
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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.