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C0550 has code c0550 ecu/ccu malfuntion replacement and reprogram

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Engine malfunction light

give us the codes that the engine light are on for and we may be able to give you a better idea of the problem
engine codes can cover many causes for the light report

Aug 01, 2016 | 2008 BMW 535i Sedan

1 Answer

Have a 2004 gmc yukon getting codes c0040, c0550,c0455,c0296 in the abs computer. Trac and abs light on as well as suspension control.

C0040 - Right Front Wheel Speed Circuit Malfunction
C0550 - ECU Malfunction - internal write / checksum malfunction
C0455 - Either:
  • A bent terminal or poor connection at the SWPS may be one possible cause; or
  • The vehicle stability enhancement system (VSES) electronic brake control module (EBCM) calibration may be the other possible cause.
C0296 - Transfer Case Delivered Torque for Stability Control System Circuit

Feb 27, 2015 | 2004 GMC Yukon

1 Answer

What would make my service abs system,service brake system,service traction system,service stability system come on with the ecu/ccu malfunction code c0550

You have to realize that your wheel speed sensor is what tells all of these systems what each wheel is doing, I would think one of these would be the problem, but without putting it on a computer you can't know which one.

Jul 26, 2014 | Cars & Trucks

1 Answer

Reprograming replaced ECU

Do they need reprograming, dont they come ready to install. I have never pre programed one. Only programed after installed in vehicle to change power curve or fuel settings not really sure what you mean

Mar 30, 2014 | 2011 Nissan Rogue

1 Answer


The C0550 means that "ECU Malfunction internal write/ checksum malfunction", luck for you!
T300+ key programmer

Jul 19, 2012 | 2004 GMC Envoy

1 Answer

2002 envoy code co550

you need to replace the tccm and get it programmed.

2-04-21-006E: Inoperative 4WD/AWD Lamps, Inoperative 4WD/AWD System, DTC C0550 Set No Communication with TCCM (Reprogram Transfer Case Control Module) - (Jul 20, 2006)
999999995.gif Subject: Inoperative 4WD/AWD Lamps, Inoperative 4WD/AWD System, DTC C0550 Set, No Communication with TCCM (Reprogram Transfer Case Control Module) Models: 2004 Buick Rainier 2002-2004 Chevrolet TrailBlazer, TrailBlazer EXT 2003-2004 Chevrolet Avalanche, Silverado, Suburban, Tahoe 2002-2004 GMC Envoy, Envoy XL 2003-2004 GMC Sierra, Yukon, Yukon XL 2004 GMC Envoy XUV 2002-2004 Oldsmobile Bravada with Electronic Shift or Active Transfer Case (RPOs NP1, NP4 or NP8)

This bulletin is being revised to add Subject information and change the labor operation. This bulletin cancels and supersedes Bulletin Number 03-04-21-006. Please discard Corporate Bulletin Numbers 02-04-21-006D and 03-04-21-006 (Section 04 -- Driveline/Axle).
ConditionSome customers may comment that the 4WD/AWD indicator lights on the selector switch do not work, or the 4WD/AWD system may be inoperative and/or the service 4WD light is illuminated. The condition is typically intermittent and always occurs at key-up. Upon investigation, the technician may find DTC C0550 set.
CauseThe Transfer Case Control Module (TCCM) has not received the wake-up call during key-up and has remained in the "sleep mode".
When the TCCM is in the "sleep mode", it will not communicate with the class II bus or the Tech 2®.
  1. Try to communicate with the TCCM. If no communication, go to step 2. If communication is possible, go to step 5.
  2. Remove the underhood (ATCM or TREC) TCCM fuse.
  3. Wait 30 seconds.
  4. Reinstall the fuse. The module should "wake up" and communicate with the Tech 2®.
  5. Check for codes in the TCCM. If a C0550 is found current or in history with or without other codes, replace the module and go to step 6.
  6. Reprogram the TCCM with the latest TIS software using normal SPS procedures.
  7. Verify operation and that no codes are present.
Important: For the 2002 model year, the TCCM must be replaced and reprogrammed.
Warranty Information

Jul 29, 2011 | 2002 GMC Envoy

1 Answer

I have 2002 envoy with service 4wd light on a code co550 ecu/ccu malfunction .where do i go

Replace the transfer case module.this module will need to be programmed by a gm dealer.Co550 is a internal fault code.bulletin from gm for this.

Dec 02, 2010 | 2002 GMC Envoy

1 Answer

Replaced crank and cam sensor on a 2004 altima 2.5 but the trouble code is still telling me the crank sensor is bad.

did you erase the the trouble codes (or reset the ecu) after replacing the sensors?

is this model included in the recall for ecu reprogramming?

Apr 29, 2010 | 2004 Nissan Altima

1 Answer

Replaced the ecm computer on 2001 dodge durango then start it up and it runs and then cuts itself off after 15 seconds

The ECU would have to be programmed from the dealer. It normally costs somewhere around $100 to have it reprogrammed. The reason it needs reprogrammed is because the factory theft module in your car is different than the theft module in the car that the "new" ECU came from. I had this problem with my 1997 Cadillac Deville.

All you would have to do is get it to a Dodge dealership and have them reprogram the ECU. Make sure you explain that you just replaced the ECU, and you need it reprogrammed to match your SUV.

Please vote on my solution whether good or bad. Thanks! :D

Oct 25, 2009 | 1999 Dodge Durango

1 Answer

2 problems...Service 4WD...(already replaced switch module!), and won't start with ~1/2 tank gas or less!

Do you know how to do scan tool diagnostic's ? Checking DTC'S - diagnostic trouble codes , viewing input data to the computers on the vehicle . The fuel sending unit is located inside the fuel tank ,it is a input to the PCM - engine computer . The PCM use's this fuel level info . to be able to conduct testing procedures for the evaporative emission system.
The Evaporative Emission Control System (EVAP) is used to prevent gasoline vapors from escaping into the atmosphere from the fuel tank and fuel system. The EVAP system usually requires no maintenance, but faults can turn on the Check Engine light and prevent a vehicle from passing an OBD II plug-in emissions test..
Shorted sensors can cause all kind of problems .including bring down the five volt reference circuit inside the PCM . Also checking for DTC'S in the 4X4 control module should have been done before replacing parts . Your best bet ,take it to a qualified repair shop.
Do you know which transfercase your vehicle has ?

The NVG 246 EAU transfer case features a 4 button shift control switch located on the instrument panel.
The BW 4482 transfer case features a 3-button shift control switch located on the instrument panel.
Just replacing parts is not the way to a fix . Both systems can set a number of DTC'S
DTC B0790
DTC B2725
DTC C0306
DTC C0327
DTC C0329
DTC C0359
DTC C0550
The NVG 246 EAU transfer case
DTC B0790
DTC B2725
DTC C0300
DTC C0305
DTC C0306
DTC C0321
DTC C0327
DTC C0359
DTC C0374
DTC C0379
DTC C0550

Do yourself a favor ,have a qualified repair shop diagnose the problem . An you can't just replace the 4X4 control module an expect it to work .It needs to be programmed .
Transfer Case Shift Control Module Reprogramming
Remote Programming Feature
Connect the scan tool to the vehicle.
Power-up the scan tool and select the Service Programming feature.
Select the appropriate vehicle.
Press the Request Info button on the scan tool.
Disconnect the scan tool from the vehicle and connect the scan tool to the computer station.
Follow the menu select items for reprogramming and provide information as to what type of device you are programming and whether you are reprogramming or replacing the electronic control unit (ECU).
Select "vehicle" from the selection menu.
Select the module you wish to Program.
Select "Normal" for Programming Type.
Select the applicable software calibrations.
Transfer data file to the scan tool.
Reconnect the scan tool to the vehicle.
Turn ON the ignition, with the engine OFF.
Select the Service Programming feature on the scan tool.
Press the Program button on the scan tool.

Jan 01, 2018 | 2003 Chevrolet Suburban 1500

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