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 MANUALSCHEVROLET1998SUBURBAN K2500, 7.4 J, PART TIMEREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 143 (ENGINE CONTROL SYSTEM SELF-DIAGNOSTICS - 3.1L ENGINE)DIAGNOSTIC TESTSDTC P0135: HO2S HEATER PERFORMANCETEST DESCRIPTION
1998 Chevrolet Suburban K2500, 7.4 J, Part Time
Test Description
1998 Chevrolet Suburban K2500, 7.4 J, Part TimeSECTION Test Description
WARNING: This page is about a different car, the 2002 Pontiac Grand Prix, 2002 Chevrolet Malibu, and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step numbers in the diagnostic procedures.
- 2
Inspect the heater current with the engine at operating temperature, and allow time for the heater current to stabilize. The HO2S 1 heater current is initially higher until the sensor reaches full operating temperature. - 4
This step ensures that the ignition voltage circuit to the HO2S 1 is not open or shorted. The test light should be connected to a good chassis ground, in case the HO2S 1 low reference or HO2S 1 heater low control circuit is malfunctioning. - 6
This step inspects the HO2S 1 heater ground circuit. The engine must be running for the PCM to enable the heater low control driver to provide a path to ground.
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.