P0147 Code Question

[Jesecourt]

First of all, I am new here and a female, so bare with me. I have a 96 Blazer 4x4 that I purchased about a month ago, and the service engine soon light has come on. Took it to Autozone and they gave me the code: P0147 (O2 sensor bank 1 sensor 3). In searching the forum, I read that this has something to do with the heater element...will it also cause a strange smell inside the vehicle when the heater is on? Thanks a bunch for any help you can give me.

[TonyMazz]

Originally Posted by Jesecourt

First of all, I am new here and a female, so bare with me. I have a 96 Blazer 4x4 that I purchased about a month ago, and the service engine soon light has come on. Took it to Autozone and they gave me the code: P0147 (O2 sensor bank 1 sensor 3). In searching the forum, I read that this has something to do with the heater element...will it also cause a strange smell inside the vehicle when the heater is on? Thanks a bunch for any help you can give me.

Welcome Jesecourt to our forum.....

I think this DTC of P0147 determines if the HO2S (heated Oxy Sensor) is functioning properly by checking for an adequate number of HO2S voltage transitions above and below the bias range of 300-600 mV.

This DTC sets when the VCM (Vehicle Control Module or your cars computer) fails to detect a minimum number of voltage transitions above and below the bias range during the test period. Possible causes of this DTC are listed below.


An open or a short to voltage on either the HO2S signal or HO2S low circuits.
A malfunctioning HO2S.
A problem in the HO2S heater or its circuit.
A poor HO2S ground.

This DTC determines if the HO2S heater circuit is functioning properly by monitoring the amount of time required for the HO2S to reach operating temperature. This DTC sets when the VCM fails to detect HO2S voltage transitions above and below the bias range within a specified amount of time. Possible cause of this DTC are listed below.


An open circuit in either the HO2S ignition feed or the HO2S heater ground circuits or an HO2S heater element problem

So the bottom line is...

Check for the following conditions:
An intermittent may be caused by any of the following conditions:

A poor connection , Rubbed through wire insulation , A broken wire inside the insulation for starters....

Hope this helps

[BlazerLT]

The O2 sensor that is bad is the one after the cat convertor and the closest O2 sensor to the rear.

It is the O2 sensor between the catalytic convertor and the muffler.

The smell from inside the cabin when the heat is on could be the heater core.

Does it smell like burnt plastic or a sweet odd smell like antifreeze.

For a comparison, take whiff of your coolant overflow tank for a comparative smell.