O2 Sensor Heater Problem

what is the fuse called for the O2 sensor? I cant find it?

Welcome to Automotive Forums!

What year, model, and engine do you have?

its a 2000 4wd 4.3 4 doors,
i have replaced 2 o2 sensors bank 1 sens 1 and the one before the cat.
and still getting error 0135

thanks for your help

Alex

its a 2000 4wd 4.3 4 doors,
i have replaced 2 o2 sensors bank 1 sens 1 and the one before the cat.
and still getting error 0135

thanks for your help

Alex
Fuse is ECMI underhood fuse box.
But if it was bad it also feeds injectors and engine would not run.

On left side engine front sensor.
Check for 4.5 volts on heater circuit to that sensor.
Post back voltage reading.

This code usually means a problem with the heater circuit, not the O2 sensor circuit......

Should be reading BAT voltage on the heater circuit......

ok i might be misunderstanding but is the heater circuit complete different from O2 sensor and if so where is it and how do i find it to test it. I am getting code 1035

thanks.

Alex

P0135 is the driver side sensor, closest to the engine, heater malfunction. The heater is part of the oxygen sensor. The electrical connector has 4 wires, 2 for the sensor and 2 for the heater. As mentioned, make sure you have battery voltage and ground at the harness connector. Black wire must be less than 5 ohms resistance to ground, and the pink wire must show battery voltage with the ignition in the RUN position. After repairing the problem, clear the DTC's and perform a drive cycle to verify the repair was successful. http://www.obdii.com/drivecycle.html

Ok so i did the test as you asked.
The bat voltage was 12v
on the wire harness i test the pink/red to ground and got 11v
for the ohms i got nothing i checked all wires to ground with ohms on and got nothing.
So what does that tell us, I read the article you included however i cleared the codes after i put the new O2 sens in is that the same type of clearing as in that article.


Thanks for all your help.

Alex

Yes one more thing where does the other side of the harness end terminate in the engine compartment.

Alex

The black wire is the ground for the heater in the sensor. You found it has an open circuit, that's what is causing the P0135. You can either trace it back until you find the break in the wire*, or you can solder on a new piece of wire and attach it to a good, clean, chassis ground. Problem solved! Good job!

* The original ground for the heater is to a bolt in the rear of the driver side cylinder head.

Clearing the DTC's will remove all DTC's from memory. Performing the drive cycle "forces" the ECM to run and complete the monitors. If all of the monitors run and complete their tests, and they all pass, the SES light will remain off.

Ok i got it. Just duno how i am going to get in there to cut it so dam tight.
Once i do they i can use an OBDII scanner to clear it and hopefully never see the check engine light come on.

You can get right at the harness connector at the sensor, there's plenty of room. First make sure the crimp connection at the black wire terminal in the vehicle harness connector is good. Then move up the vehicle harness, a couple of inches away from the connector, and solder on a new piece of wire. Solder on an eyelet connector and attach it to ground.

ok just want to be clear on which black wire to cut i dont think it matters but i rather ask first then cut once.

I am going to cut the black wire between the o2 sensor and its connector.
then run that to ground and plug the harness back in.
then using an OBDII scanner clear the code.

Thanks

Alex

In the vehicle harness connector to the sensor, there is only one black wire. Follow that wire through the connector and into the sensor. Remove about a half inch of insulation, (don't cut the wire) between the O2 sensor and its connector. Solder on a piece of wire and run it to ground. IF the crimp is the problem, doing it this way will bypass the crimp. This will also make it more difficult to replace the sensor in the future if necessary, but it eliminates a connection as a possible problem. It's very important to solder the connection and insulate it, DO NOT use a crimp connector.

ok so i finally had time to get back in to this projected. I added the new ground wire it looks good i will have a friend with a code scaner clear the code for me and see if it comes back. I found many other issues with this truck that leads me to believe the did stuff to it to pass smog. I found the main air in take and the rear vacuum line not attached. I have bolted it down and re attached the removed vacuum line. I dont need it to pass smog for aleast a year but as i work on it i find more things that make me go hummmm.

Thanks for your help i will let you know if the code comes back.

ok so after all that the check engine light has come back. What should i look at next?

Alex

Have your friend check "I/M Readiness" status on his scan tool. Make sure all monitors are complete. If not, perform a drive cycle to force them to complete: http://www.obdii.com/drivecycle.html If they are complete, retrieve all DTC's and post them in the order they are retrieved.

Hello,

Sorry for the long delay, so i got the scanner and belive i checked the right thing.
This is what it said:
Bank one sensor one 02 heater circuit malfunction P1035

Thats what it said under the I/m readiness but dont seem right?
Does that help?

Thanks

Alex

Hello,

Sorry for the long delay, so i got the scanner and belive i checked the right thing.
This is what it said:
Bank one sensor one 02 heater circuit malfunction P1035

Thats what it said under the I/m readiness but dont seem right?
Does that help?

Thanks

Alex

What do you think is not right?

If code was cleared and came back after driving ten you have a problem for that code.
Check voltage and ground and wiring/plugin for that sensor.

ok so i did some reading up and figured out that you are looking for what service are ready and not ready so this is what i found

Not ready
Catalyst
Evap sys
Ho2 sensor

Not applicable
Ac refrig
Sec air
Heated cat

Does that help?

ok so i did some reading up and figured out that you are looking for what service are ready and not ready so this is what i found

Not ready
Catalyst
Evap sys
Ho2 sensor

Not applicable
Ac refrig
Sec air
Heated cat

Does that help?

That is telling you you have not drove it enought for the computer to do all of it testing.
Like cat test and 02sensor test and EVPA system.

If all codes were cleared drive it long enought for the computer to run all test and then chek forwhat codes you have.
Post back code no that comes back.

Ok so i just did a drive cycle and it must have worked becuae all I/M readiness everthing is eaither ready or not applicable, However the check engine light is still on. So do i need to clear the code? or do another drive cycle test or just leave it for a bite and see if it clears.

I dont want to clear it just for it to come back again and have to start over again.

Thanks again..

Alex

Ok so i just did a drive cycle and it must have worked becuae all I/M readiness everthing is eaither ready or not applicable, However the check engine light is still on. So do i need to clear the code? or do another drive cycle test or just leave it for a bite and see if it clears.

I dont want to clear it just for it to come back again and have to start over again.

Thanks again..

Alex
I am sorry if that is to much work and trouble for you.
BUT.
Clearing codes after repair is just part of the repair procedure.
Clearing codes lets the VCM go threw all of it self test and then it can tell you if every thing is A OK
Clear code and drive it and if code comes back you still have a problem.
If it runs good and no codes after self test and no check engine light all is well.

Ok i cleared the codes a few days ago and now the check engine light has come back!
I scanned it and got the same code p1035 bank 1 sensor 1.

I/M says either ready or not applicable.

Any further info would help..

Thanks..

Ok i cleared the codes a few days ago and now the check engine light has come back!
I scanned it and got the same code p1035 bank 1 sensor 1.

I/M says either ready or not applicable.

Any further info would help..

Thanks..

P1035 or P0135?
Was it a present or history code?
P0135 is heater circuit for bank 1 sensor 1.

Recheck voltage to sensor and ground and wiring and plugin.
Have you by passed the plugin with soldered wires?
What is the voltage reading to sensor?

Switch 02 sensors and see if problem moves with sensor switch.

The code can also be caused by MAF sensor and several other sensor problems to.
Make sure all other sensors are in good working order.

There is a repair flow chart for that code in All Data and mitchell and GM repair manuals.
If all else fails get the repair flow chart for that code and go all of the way threw it untill you find the problem.

Let us know what you find.

ok so i had time again to get back in to this. I have pulled the O2 sensor out and put in a know good one. I also checked continuity from o2 connector to sensor and i dont believe black is the ground i think its gray because from the gray wire to the body of the connector i got continuity. see the pictures its a bosh 15703 sensor.

Also the sensor is all black, i spoke to someone and they said this is a sign of coolant getting in to the engine and it needs a new intake casket.

Alex

ok so i had time again to get back in to this. I have pulled the O2 sensor out and put in a know good one. I also checked continuity from o2 connector to sensor and i dont believe black is the ground i think its gray because from the gray wire to the body of the connector i got continuity. see the pictures its a bosh 15703 sensor.

Also the sensor is all black, i spoke to someone and they said this is a sign of coolant getting in to the engine and it needs a new intake casket.

Alex

Black on body wiring plug in is back/ground.
Bank one sensor one is grounded to left rear cylinder head.
Bank one sensor 2 is grounded right front engine block.
The o2 sensor has a different color code.

What code no are you getting?

Is sensor is black on tip engine is running rich.
Oily or wet on end you have other problem.

What parts place are you getting sensor and sensor no from?

Drove the truck to work today about 7 miles, when leaving working check engine light came back on. Its code P1305 which is bank one sensor one( driver side sensor ). But no code for the o2 sensor that is missing which is the first one on the passenger side. So something major is wrong. I am either working on the wrong sensor, or something is miss wired back to the computer module. Any ideas?

Drove the truck to work today about 7 miles, when leaving working check engine light came back on. Its code P1305 which is bank one sensor one( driver side sensor ). But no code for the o2 sensor that is missing which is the first one on the passenger side. So something major is wrong. I am either working on the wrong sensor, or something is miss wired back to the computer module. Any ideas?

P1305ChevroletIgnition Coil 2 Primary Feedback Circuit

If we are talking about P0135, disconnect that sensor....attach a test light to the "heater circuit" on the harness side leading to the VCM.....start the vehicle(cold) and see if the test light, lights....the purpose of the heater circuit is to get that sensor up to temp quickly, so that it will start operating sooner and the engine goes into closed loop faster.....this code sets when the VCM sees that it is taking too long for that sensor to start operating....the code has nothing to do with the MAF.....

If it doesn't light, that fuse and circuit has to be checked out.....if nothing wrong, then we may be talking VCM....