How to Diagnose a P0135 -Heater
Performance Bank 1 Sensor 1 (GM 3.5L)
January 31, 2012 Updated: October 29, 2014 Written by: Abraham Torres-Arredondo Article Id: 371
If your check engine light is on and you have a diagnostic trouble code P0135 stored in the PCM's memory... then you've come to the right place to test and troubleshoot the upstream oxygen sensor.
A P0135 DTC says: HO2S Heater Performance Bank 1 Sensor 1... and this means that the PCM (Powertrain Control Module = Fuel Injection Computer) has detected a problem with the front oxygen sensor's heater element or a problem in the heater's circuit (wires).
In this tutorial, I'll show you how to check the oxygen (O2) sensor's heater element and the two circuits that feed it with power (10 to 12 Volts) and ground with a multimeter.
In case you're wondering, where the oxygen (O2) sensor that the code P0135 is accusing of being BAD is... this bad boy is located on the exhaust manifold and before the catalytic converter.
To help you navigate this article, here are its main points:
Buying a Digital Multimeter for Automotive Diagnostic Testing
- Symptoms of a BAD Oxygen Sensor Heater Element.
- What Tools Do I Need to Test Code P0135?
- What Does the Heater Inside the Oxygen Sensor Do?
- Circuit Descriptions of the Downstream Oxygen Sensor.
- Start Here.
- TEST 1: Oxygen Sensor Bank 1 Sensor 1 Test.
- TEST 2: Checking 12 Volts to O2 Heater.
- TEST 3: Checking the O2 Heater's Ground Circuit.
- TEST 4: Ohming the O2 Heater Element.
- P0135 O2 Sensor Heater Test Summary.
(found at: easyautodiagnostics.com).
Wire Piercing Probe.
- Don't have one?... check out my recommendation: Abe's Scan Tool Recommendation.
- Although this tool is not an absolute must, if you do buy one, you'll realize just how easy it makes testing the voltages inside the wires.
- If you need to see what this tool looks like, you can see it here:Wire Piercing Probe.
How To Test for a Blown Head Gasket (GM 3.5L, 4.2L)
How to Test the MAF Sensor and Codes: P0100, P0101, P0102, P0103
How To Test for a Blown Head Gasket (GM 3.5L -FWD)
All Articles: 3.5L
- Colorado 3.5L
"A day without sunshine is like, you know, night"