HVAC fault codes question.

[gregsmy]

Did a little work with my AC issues. One of my possible issues might have had to do with the actuators. So I connected my bi-directional scan tool and checked for codes and ran the learn function for the actuators as well as a few other tests. There where a number of codes stored in the system. I went ahead and ran a report and then erased codes. There are a number of codes that just comeback immediately, like a hard fault. Looking for any insight as to what the problem might be. These are the codes listed under the HVAC control module:

B0413-04 Temperature control 1 feedback circuit open
B0433-04 Temperature control 3 feedback circuit open
B3782-04 Air flow control 10 feedback circuit open

The HVAC seems to operate normally other than my low freon situation.

There is also a code listed for the Body Control Module that keeps coming back:

U0200-00 Lost communication with the door control module B

And a couple listed for the Vehicle Comm. Interface Module:

B1000-3C Electronic control unit (ECU) performance
B2470=04 Cellular phone antenna open circuit

And a code under the Engine Control Module:

P0521-00 Engine oil pressure sensor performance

This one relates to the weird situation I have with my oil pressure gauge. Most of the time the gauge reads correctly, but occasionally the needle will swing back and forth like 20 pounds. I was planning on starting a separate post in the engine section about this problem and what I have already done and replaced.

 

[OR VietVet]

And a code under the Engine Control Module:

P0521-00 Engine oil pressure sensor performance

This one relates to the weird situation I have with my oil pressure gauge. Most of the time the gauge reads correctly, but occasionally the needle will swing back and forth like 20 pounds. I was planning on starting a separate post in the engine section about this problem and what I have already done and replaced.


@gregsmy, use your scanner live data function and get the voltage readings for your oil pressure. That will tell you if the sender/sensor is working or not. If that is accurate, then, like my recent oil pressure fluctuation problems, the stepper motor in the dash cluster is likely the problem. Then find a cluster fixer upper or do some digging on replacing the stepper motor yourself.

See oil pressure voltages below:

 

[gregsmy]

And a code under the Engine Control Module:

P0521-00 Engine oil pressure sensor performance

This one relates to the weird situation I have with my oil pressure gauge. Most of the time the gauge reads correctly, but occasionally the needle will swing back and forth like 20 pounds. I was planning on starting a separate post in the engine section about this problem and what I have already done and replaced.


@gregsmy, use your scanner live data function and get the voltage readings for your oil pressure. That will tell you if the sender/sensor is working or not. If that is accurate, then, like my recent oil pressure fluctuation problems, the stepper motor in the dash cluster is likely the problem. Then find a cluster fixer upper or do some digging on replacing the stepper motor yourself.

See oil pressure voltages below:

View attachment 450819

I will see if I can find that information with my scan tool. Did you have a thread on your issue?

 

[Fless]

2007-up should have a PID for oil pressure; there shouldn't be a need to convert sensor voltages.

 

[OR VietVet]

@Fless gave me that voltage info but that was for a 2004 Silverado

 

[swathdiver]

Did a little work with my AC issues. One of my possible issues might have had to do with the actuators...

What are you driving friend?

 

[Fless]

What are you driving friend?

2010 Suburban from his other thread: https://www.tahoeyukonforum.com/threads/ac-charge-question.153110/

It would be helpful to have vehicle info in the signature so it's always there to reference.

 

[swathdiver]

Did a little work with my AC issues. One of my possible issues might have had to do with the actuators. So I connected my bi-directional scan tool and checked for codes and ran the learn function for the actuators as well as a few other tests. There where a number of codes stored in the system. I went ahead and ran a report and then erased codes. There are a number of codes that just comeback immediately, like a hard fault. Looking for any insight as to what the problem might be. These are the codes listed under the HVAC control module:

B0413-04 Temperature control 1 feedback circuit open
B0433-04 Temperature control 3 feedback circuit open
B3782-04 Air flow control 10 feedback circuit open

The HVAC seems to operate normally other than my low freon situation.

There is also a code listed for the Body Control Module that keeps coming back:

U0200-00 Lost communication with the door control module B

And a couple listed for the Vehicle Comm. Interface Module:

B1000-3C Electronic control unit (ECU) performance
B2470=04 Cellular phone antenna open circuit

And a code under the Engine Control Module:

P0521-00 Engine oil pressure sensor performance

This one relates to the weird situation I have with my oil pressure gauge. Most of the time the gauge reads correctly, but occasionally the needle will swing back and forth like 20 pounds. I was planning on starting a separate post in the engine section about this problem and what I have already done and replaced.

Keep your GM vehicle all GM. The computers in these trucks don't like aftermarket components.

All of those actuators are in need of replacement if those are current and not historical codes.

B1000 C3, Your ECM has an internal short and ought to be replaced.

U0200 00, Might be related to the B1000, don't know, it's not in my list.

P0521 00, You need a new oil pressure sensor. If AFM is active, replace the filter underneath it too.

B2470 04, I used to get this one. It was caused by water getting past the roof antenna and running down the celluar coax cable. Code went away when it dried out. A thin bead of clear RTV around the base of the antenna fixed this. Car Washes wear away the RTV over time, beware.

 

[OR VietVet]

So, I guess the oil pressure voltage readings that @Fless gave me, are for GMT800 trucks?