Hyundai Forums banner

1 - 20 of 59 Posts

·
Registered
Joined
·
62 Posts
Discussion Starter #1
I have a 2007 Sonata 3.3...I had to replace the middle pipe (one with two flex pipes on it)...When I got it all back together I got the P0057 code...I went ahead and replaced the O2 sensor..but that did not fix it...I have checked the O2 sensor and it is working as it should...I also have power (+12V) and Ground at the female connector for the O2 sensor...I tried swapping the PCM with another 2006 Sonata 3.3 and get the same message....when I put the 2007 PCM in the 2006 it runs fine which leads me to believe the PCM is functional....

So...I have no idea what could be wrong.....

Anyone?????
 

·
Registered
Joined
·
4,979 Posts
I have a 2007 Sonata 3.3...I had to replace the middle pipe
Why, was it rusted out? Did you replace it yourself?


I have checked the O2 sensor and it is working as it should.
How did you check it?

That code may be from a leak in the system prior to the B1S1.
 

·
Registered
Joined
·
11,888 Posts
That code may be from a leak in the system prior to the B1S1.
P0057 could be caused by an exhaust leak on bank 1?

The code points to an O2 heater circuit failure on the downstream sensor on bank 2. I don't follow your logic?

I have no idea what could be wrong.....
Anyone?????
Assuming you replaced the correct sensor, the fault is likely in the wiring between the bank2 downstream O2 sensor and the PCM. You say the sensor has a 12V supply which sounds good, but you need to check the heater control wiring coming from the PCM. That isn't a ground (or shouldn't be). It's a PWM (Pulse Width Modulated) signal.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #8
Thanks for the info.

Now that you mention it. When I used a known good PCM I still get the P0057. So, that tells me (I think) that you are correct. There is a fault between the sensor and the PCM. So, again, (I think), I should test the wire(s) between the sensor and PCM.

How do I check the wiring between the sensor and the PCM? I have access to both downstream sensor wire harnesses. They junction right at the top of the engine. I have no idea what color they are or how to test them.
 

·
Registered
Joined
·
11,888 Posts
I don't know what colour the wires are in the car's wiring harness, but if you look at the wires on the sensor side of the connector you'll probably find a black, a grey and two white wires. The two white wires are the heater circuit. Now just look to see what wires on the harness align with the white wires on the sensor and you'll then know what colours your looking for.

The first step I would take is to connect a 12V bulb across the two heater terminals on the sensor harness connector. When you start the engine the bulb should start to flash. The bulb flashing would suggest the wiring is OK. The flashing is caused by the PCM's PWM control signal. If the bulb doesn't light at all that suggests the wire is open circuit/broken somewhere between the sensor and the PCM. And if it lights up continuously that suggest the wiring has shorted to ground, which usually means the wiring has chafed on the the engine block or car body somewhere.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #10
I don't know what colour the wires are in the car's wiring harness, but if you look at the wires on the sensor side of the connector you'll probably find a black, a grey and two white wires. The two white wires are the heater circuit. Now just look to see what wires on the harness align with the white wires on the sensor and you'll then know what colours your looking for.

The first step I would take is to connect a 12V bulb across the two heater terminals on the sensor harness connector. When you start the engine the bulb should start to flash. The bulb flashing would suggest the wiring is OK. The flashing is caused by the PCM's PWM control signal. If the bulb doesn't light at all that suggests the wire is open circuit/broken somewhere between the sensor and the PCM. And if it lights up continuously that suggest the wiring has shorted to ground, which usually means the wiring has chafed on the the engine block or car body somewhere.
Thanks so much. I return on Friday, will check it out and report back.

Thanks again....I am at a loss...
 

·
Registered
Joined
·
62 Posts
Discussion Starter #11
Thanks so much. I return on Friday, will check it out and report back.

Thanks again....I am at a loss...
I don't know what colour the wires are in the car's wiring harness, but if you look at the wires on the sensor side of the connector you'll probably find a black, a grey and two white wires. The two white wires are the heater circuit. Now just look to see what wires on the harness align with the white wires on the sensor and you'll then know what colours your looking for.

The first step I would take is to connect a 12V bulb across the two heater terminals on the sensor harness connector. When you start the engine the bulb should start to flash. The bulb flashing would suggest the wiring is OK. The flashing is caused by the PCM's PWM control signal. If the bulb doesn't light at all that suggests the wire is open circuit/broken somewhere between the sensor and the PCM. And if it lights up continuously that suggest the wiring has shorted to ground, which usually means the wiring has chafed on the the engine block or car body somewhere.
This may be a dumb question, but, anyway here goes.

Should I have spliced into the wires while the harness is connected?

I disconnected the harness and hooked up the 12V bulb across the two heater circuit wires. First I did the PCM side of the harness then the sensor side of the harness and the light did not light at all.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #12
This may be a dumb question, but, anyway here goes.

Should I have spliced into the wires while the harness is connected?

I disconnected the harness and hooked up the 12V bulb across the two heater circuit wires. First I did the PCM side of the harness then the sensor side of the harness and the light did not light at all.
Ok, I went ahead and spliced into the wire. Still no light.

So, I will troubleshoot the open circuit between sensor and PCM.

Thank you!
 

·
Registered
Joined
·
11,888 Posts
Should I have spliced into the wires while the harness is connected?
Sorry my reply is a bit late, but no, you didn't need to do that.

pbennison said:
I disconnected the harness and hooked up the 12V bulb across the two heater circuit wires. First I did the PCM side of the harness then the sensor side of the harness and the light did not light at all.
It's the PCM (harness) side you connect it to. There wouldn't be anything on the sensor side.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #14
Sorry my reply is a bit late, but no, you didn't need to do that.


It's the PCM (harness) side you connect it to. There wouldn't be anything on the sensor side.
Thanks...I am back at it. Is there a way to check where the two heater wires connect at the PCM? I am assuming since the light did not light up that one of the two sensor wires is broken between the harness and PCM.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #15
Thanks...I am back at it. Is there a way to check where the two heater wires connect at the PCM? I am assuming since the light did not light up that one of the two sensor wires is broken between the harness and PCM.
Ok, now I am really confused.

When I hook up my voltmeter I show 12V across heater circuit with key on and/or engine running. When I hook up light bulb on that circuit voltage drops to zero.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #16
Sorry my reply is a bit late, but no, you didn't need to do that.


It's the PCM (harness) side you connect it to. There wouldn't be anything on the sensor side.
Sorry to keep bothering you. Should I do anything with the other two wires at the harness when checking with the light bulb? I am currently unhooking the harness and just connecting the bulb across the heater circuit.
 

·
Registered
Joined
·
11,888 Posts
When I hook up my voltmeter I show 12V across heater circuit with key on and/or engine running. When I hook up light bulb on that circuit voltage drops to zero.
That means there is a high resistance in the circuit. Ohm's Law tells us that the voltage drop across a resistance is proportional to the amount of current that is flowing through it. When the circuit is open (disconnected) there is no current flow and therefore no voltage drop, so you get 12V. Connecting the bulb causes current to flow which creates voltage drop. That's what your seeing on your meter.

When the bulb is connected across the heater circuit have you tried connecting your voltmeter between the heater power supply terminal and the car body (ground) to check that the 12V supply isn't dropping out? That will tell you what side of the circuit has the resistance. If the 12V disappears when the bulb is connected the fault/resistance is on the power supply side of the circuit rather than the control side.

Should I do anything with the other two wires at the harness when checking with the light bulb? I am currently unhooking the harness and just connecting the bulb across the heater circuit.
No, you shouldn't need to do anything with the other two wires.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #18
That means there is a high resistance in the circuit. Ohm's Law tells us that the voltage drop across a resistance is proportional to the amount of current that is flowing through it. When the circuit is open (disconnected) there is no current flow and therefore no voltage drop, so you get 12V. Connecting the bulb causes current to flow which creates voltage drop. That's what your seeing on your meter.

When the bulb is connected across the heater circuit have you tried connecting your voltmeter between the heater power supply terminal and the car body (ground) to check that the 12V supply isn't dropping out? That will tell you what side of the circuit has the resistance. If the 12V disappears when the bulb is connected the fault/resistance is on the power supply side of the circuit rather than the control side.


No, you shouldn't need to do anything with the other two wires.
Thank you for being so patient. I just checked and hooking up bulb, I still have power at the supply and car body.
 

·
Registered
Joined
·
62 Posts
Discussion Starter #19
I have a service manual with some wiring diagrams, but, it does not have the information of how the wire from the harness gets to the PCM. From what I can tell the two wires look like they are Blue and Pink going to PCM.

Is there any way to determine what these two wires correspond to on the PCM connector? There are two large connectors going into PCM. Looks like one goes to fuse box other one is coming in from engine bay. I hate to start messing around and playing with those two harnesses without actually knowing where to start.
 

·
Registered
Joined
·
11,888 Posts
Is there any way to determine what these two wires correspond to on the PCM connector?
There will only be one wire in the heater circuit that connects to the PCM, the control wire. The other wire is a power supply and that one will connect to the fusebox (usually SNSR fuse).


pbennison said:
There are two large connectors going into PCM. Looks like one goes to fuse box other one is coming in from engine bay.
The sensor wiring is usually on the connector coming from the engine. But the diagram will tell you what connector it is and exactly what terminal on the connector the heater control wire connects to. Unfortunately I don't have a diagram for the 3.3 engine because, AFAIK, it was never offered here in the UK.

If you follow the line representing the heater control wire on the diagram from the O2 sensor to where it meets the PCM you should see a number next to the line. That is the terminal number on the connector the wire connects to. If you look to the right of that number you should come to another number in a bold font, usually prefixed by the letter 'C'. That number identifies the harness connector. It'll be something like C44 for example. The letter 'C' tells us the connector is part of the engine Control harness. So now you know what connector and terminal the wire connects to you should now find the pinout diagram of that connector. The pinout diagram will show you where on the connector the heater control terminal is located.

Does that make it any clearer, or have I just made things worse :)
 
1 - 20 of 59 Posts
About this Discussion
58 Replies
4 Participants
pbennison
Hyundai Forums
Hyundai Forum is a community for all Hyundai Owners to talk and learn all about their favorite subject: Hyundai cars from the Sonata to the Elantra and even the new Kona!
Full Forum Listing
Top