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Pete
Pete, Auto Service Technician
Category: Chevy
Satisfied Customers: 29118
Experience:  14 years GM dealer Technician.
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I have a 2009 2500hd 4x4 diesel. My 4x4 won't engage. It

Customer Question

Hello I have a 2009 2500hd 4x4 diesel. My 4x4 won't engage. It says service 4x4 on the message board on the dash. The switch lights up when you first turn the truck on but then it turn off. Also my transmission won't engage any gears. The linkage moves fine but it's like it's not catching any gears. If I try to put it in park while the truck is running it sound like it grinds really bad. When it is in park you can roll the truck forward and backwards same with reverse neutral drive and manual
Submitted: 2 months ago.
Category: Chevy
Expert:  Pete replied 2 months ago.

Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.

Both of these issues are most likely related.Your transmission is no longer holding the vehicle when in park.This can be caused by a mechanical fault in the transfer case or transmission or even a drive line or U joint failure.This also causes the no gear engagement and grinding when shifted.

The drive line and U joints need checked and if found to be o.k. check the fluid in the transfer case for metal debris or being black and burned as this indicates internal transfer case failure.In allot of cases the transfer case has to be removed to inspect it internally to locate any mechanical issues.

If it is found to be o.k. then the transmission will need inspected internally for mechanical failure.Possibly a broken output shaft as this will cause this fault as well.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service,your 5 star rating is appreciated ( should be a link to click on here or above).You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete

Customer: replied 2 months ago.
But I don't understand how it just broke out of nowhere. I drove it to the store one night no issues and the next day it won't go into any gears
Expert:  Pete replied 2 months ago.

Does the shifter feel o.k. when shifting in and out of park?Meaning does it feel loose or like it is actually shifting the transmission?

Let me know,thanks Pete.

Customer: replied 2 months ago.
It feels normal to me
Expert:  Pete replied 2 months ago.

O.k.,if you did not hear any noises the last time it was driven the only thing I can see on the allison transmisison in this model here is a possible fault with the transfer case encoder motor.This is an electronic shift actuator on the transfer case.The sensor in it fails and causes the motor in this actuator to shift the transfer case into neutral.This will also cause all of these issues here.

Start with having the fault codes checked in the transfer case computer.This has to be done with a scan tool that will plug into your vehicles data port that can read the transfer case computer for codes.Some cheaper code readers or scan tools will only read the engine computer so you want one that can read all computers.There should be a code set for the transfer case encoder motor/actuator at fault that will help pinpoint it as the cause.

If found to be faulty it has to be replaced.Once replaced then the fault codes need reset with a compatible scan tool to then allow the 4wd switch lights to operate again.This was a common component to fail and causes this fault here.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time,this can be done at any time and you can still come back here and reply if needed.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
The two codes I got from the transfer case are C0396 and C0569
Expert:  Pete replied 2 months ago.

I apologize for the delay.

C0369 is a fault with the position sensor in the transfer case electric shift actuator itself.If this sensor is failing it causes this code to set here.On some models the sensor can be purchased separate from the actuator and the actuator removed and taken apart to be replaced.On others the entire actuator has to be replaced as an assembly.This was a common fault.

C0569 will set when the transfer case computer is unable to learn in the actuator sensor on the transfer case.This can be due to the sensor at fault in the actuator and once the sensor or actuator is replaced this will resolve this fault here as well.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time,this can be done at any time and you can still come back here and reply if needed.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
Do you have a picture of that actuator?
Expert:  Pete replied 2 months ago.

No problem

https://www.dropbox.com/s/6cvou2tdp95ntqa/act-08-08.gif?dl=0

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time,this can be done at any time and you can still come back here and reply if needed.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
Mine only has 3 boot holes to hold it to the transfer case
Customer: replied 2 months ago.
Bolt*
Expert:  Pete replied 2 months ago.

Some are different depending on the transfer case.In this case it removes and reinstalls the same way.If you do decide to take it apart to replace just the sensor make sure you mark the gear alignment up perfectly inside of it so you can reinstall the gears properly.Usually the front driveline has to be removed to access and remove it.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time,this can be done at any time and you can still come back here and reply if needed.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
This actuator is at the back or the transfer case facing the rear axle though
Expert:  Pete replied 2 months ago.
Customer: replied 2 months ago.
Yessir. Is the sensor inside the motor section of it?
Expert:  Pete replied 2 months ago.

O.k.,on this model the sensor is inside the motor and does not look like it can be replaced separate,the actuator itself has to be replaced as a complete assembly.You can get this from a dealer or a local parts store in most cases.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time,this can be done at any time and you can still come back here and reply if needed.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
Is there any special procedure for replacing it?
Customer: replied 2 months ago.
I replaced the part and there is no difference. I am throwing two codes. C0569 and B0790
Customer: replied 2 months ago.
I really need help figuring this out
Expert:  Pete replied 2 months ago.

Did you clear out the fault codes now that it has been replaced to see if any of the codes come back and to see if the 4wd then operates properly?Did you shift in and out of 4wd high and 4wd low gears at all?

Customer: replied 2 months ago.
The switch on the dash still doesn't light up to show that it's in anything. I tried to do the relearn but it won't work. I've tried clearing the codes and it doesn't work. I keep getting the C0569
Customer: replied 2 months ago.
It won't shit at all the switch doesn't show weather it's on 2hi 4hi or 4low.
Expert:  Pete replied 2 months ago.

Here is the relearn that is needed.If this is not performed this can cause this issue.If this was already done let me know.

ransfer Case High/Low Clutch Reset

Using a Scan Tool

1. Turn the ignition on go to the special functions heading in the scan tool.
2. Select Clutch Reset Procedure (Motor Learn Procedure).
3. When the Clutch Reset Procedure is initiated you should hear the motor engage, indicating a successful learn procedure.

Using The Transfer Case Shift Control Switch

1. Turn the ignition to accessory, place the switch into the 2 high mode.
2. Turn the switch clockwise past 4 low into the neutral request mode and hold for 30 seconds.
3. An audible noise from the motor should occur indicating a successful learn procedure.

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time,this can be done at any time and you can still come back here and reply if needed.Your 5 star rating is appreciated

Thanks Pete

Customer: replied 2 months ago.
My 4wd switch on the dash doesn't illuminate showing what it's in. And when I turn it all the way past 4low to N it doesn't do anything. I'm still throwing the C0569 code
Expert:  Pete replied 2 months ago.

Clear the code and see if it comes right back.Then perform this procedure below.If this does not resolve this fault let me know so we can continue:

DTC C0569

Diagnostic Instructions

- Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic approach.
- Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0569 4B: System Configuration Error Calibration Not Learned

Circuit/System Description

- This is an internal fault detection of the transfer case shift control module (TCCM). No external circuits are involved.
- This DTC is set anytime a TCCM is replaced or reprogrammed.
- The automatic transfer case (ATC) motor learn procedure must be performed in order for the TCCM to learn current clutch tolerance based on clutch stackup and accumulated clutch wear.

Conditions for Running the DTC

- Ignition ON.
- System voltage 10.5-18 V.

Conditions for Setting the DTC

The ATC motor learn procedure for a new or reprogrammed TCCM has not been performed.

Action Taken When the DTC Sets

- Mode shifting is disabled until the ATC motor learn procedure has been performed.
- The SERVICE 4WD indicator illuminates.
- No mode position LEDÆs illuminated.

Conditions for Clearing the DTC

The TCCM clears the DTC once the ATC motor learn procedure has been successfully performed.

Circuit/System Verification

1. Key ON, engine ON. Let engine run for at least 1 minute.
2. Key OFF for at least 30 seconds to allow for the complete shutdown of the TCCM.
3. Key ON, engine OFF.
4. Verify that DTC C0387 is not set.
- If DTC C0387 is set, diagnose it first.
5. Verify that DTC C0569 is not set.
- If DTC C0569 is set, perform the ATC motor learn procedure. Refer to Transfer Case High/Low Clutch Reset.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Transfer Case High/Low Clutch Reset

Let me know if you need anything else and feel free to rate my help here or above ( should be a link to click on ) as this is how I receive credit for my time,this can be done at any time and you can still come back here and reply if needed.Your 5 star rating is appreciated

Thanks Pete