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Diagnostic trouble code

U2105 lost communication with ecm buick lacross 3.6l car wont start

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6 Suggested Answers

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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: key will not start my 95 buick park avenue

does your key have a chip on it ? if it does , the problem is going to be that ,key chip only works with the original computer , until you have it reprogrammed by the dealer . this is an anti theft function to keep someone from stealing your car . there fore your car will not start until the chip matches the ecm.

Posted on Dec 08, 2008

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SOURCE: Auto Diagnostic Trouble Code

cORRECT. tHIS CODE DOES DEALs With emmissions. P1400 deals with the EGR valve. In case u are not aware, EGR stands for Exhaust Gas Re-circulation. What really this valve does is that it re-cycles some of the exhaust gases into the cylinder for combustion. The EGR valve might be blocked or has malfunctioned. It is advised that this valve changed or consult with a mechanic who is knowledgeable about this technology. a malfunctioned/dis-abled EGR system will cause the car to fail an emissions test, and may cause the EGR passages in the cylinder head and intake manifold to become blocked with carbon deposits, necessitating extensive engine disassembly for cleaning. So it is advised that u repair this ASAP

Posted on Jan 19, 2009

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SOURCE: dim headlights on 2006 buick lacrosse

check the earth wire first,wattage on the bulbs in case their wrong or old type bulbs ,check supply voltage ,if all ok then fit aux spot lights .if still having a problem have eyes checked as over 40 the old peepers can deteriorate ,dont know the name of it but it can affect some people at a younger age than others,glasses will not correct this problem.

Posted on Feb 13, 2009

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SOURCE: My remote won't start my 2005 Buick LaCross. I

Both my remotes no longer work. I will be ordering new ones off Ebay and having my dealer program them. New ones from Buick are very pricey.

Posted on Oct 20, 2009

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SOURCE: I own a 1996 buick

It's when the security light starts flashing that the infamous "chip" in the key becomes a nightmare to many. Gradually the car begins not cranking anymore or if it cranks it would start and die in a second. Randomly it will do this more and more often until it won't start anymore. VATS, PASSkey and Passlock immobilizer systems are killing cars all over North America, they have a short lifespan and are certainly more effective against owners than thieves. Here is how you save your car
1st trick, Try a spare key that is newer or used less. The pins wear down and so do the keys causing security fail. 2nd trick, (if not starting) turn the key forward 2 clicks till right before it would normally start, leave like that for 10 minutes. ( no less ) After 10 minutes, turn key back then forward and your car might start. I did this in my regal for more than a year. If its shutting down while running, im sorry i have no quick fix... If anything on this page helps you, please remember to comment or give me a thumbs up on the myfixya sight so i can have a better rating to help more people on this. Thanks

Cheap fix: Bypass the chip in your key. Temporary, but effective. Until the TDM (theft deterrent module) in the dash poops out, then you're kinda screwed. I was told that these types of key security systems have a 7-10 year life span. Sucks for us. This link explains the "Key Issue" pretty well.

Never worry again fix: Bypass the whole VATS/Passlock/passkey I or passkey II system entirely. Literally take it out, and throw it away. I just did this in my Regal. Took about an hour. Took longer to find the thing than it did to fix the problem. They sell a unit for 200 bucks to totally bypass this system FOREVER. life time-money back and all that. Finally did this in my car. Well worth the 200 if you've looked into getting this replaced... Anywhere from 600-1000 bucks. If you do buy this, please purchase it thru this link. The cost is the same, but i get credit for the sale and im trying to earn my money back, as you will be able to do if you buy fron NewRockies and join the free affiliate program. Thanks
----- ----- With this fix, you can take that whole Vats, passlock, passkey system out of your car all together. Good info on both sites.

It works for:
Any GM or Isuzu Vehicle with VATS or PASSKey or PASSLock security systems.
If your car has the chip in the key or in the lock cylinder, then you can save it with this Full Bypass.
1998-2006 S10/T10/Sonoma
1998-2007 Suburban/Avalanche
1998-2006 Sierra/Silverado
2002-2008 Trailblazer
2003-2006 SSR
1998-2006 C1500/C2500/C3500
1998-2006 K1500/K2500/K3500
2003-2007 Hummer H2
1998-2000 Hombre
2005-2006 I280/I350
2007-2008 I290/I370
2003-2007 Ascender
1994-2003 Grand Prix
1998-1999 Montana
2006 Torrent
1996-2005 Grand AM
1994-1998 Trans Sports
1988-1999 Bonneville
1988-2002 Firebird
1995-2005 Sunfire
1996-2002 Trans Am
2004-2007 Rainier
1994-2005 Century
1993-2004 Regal
1982-1999 LeSabre
1991-1996 Park Avenue / Ultra
1994-1996 Roadmaster
1991-1996 Roadmaster Estate Wagon
1982-1999 Riviera
1988-1991 Reatta
1996-1998 Skylark
1982-1990 Electra (all models)
1996-1998 Achieva
1999-2004 Alero
1994-2004 Aurora
1998-2004 Bravada
1991-1993 Delta 88
1994-1999 Eighty-Eight
1991-1996 Nighty-Eight
1998-2002 Intrigue
1990-1992 Toronado
1994-1997 Cutlass Supreme
1997-1999 Cutlass
1997-1999 LSS/Regency
1997-1999 Silhouette
1991-1996 Custom Cruiser
1998-2005 Astro/Safari
1998-2008 Envoy
2005-2006 Equinox
1998-2007 Savana/Express
1995-2005 Monte Carlo
1997-1999 Venture
1995-2001 Lumina
1988-2002 Camaro
1995-2005 Cavalier
1982-2004 Corvette
1994-1996 Caprice/Caprice Wagon
1995-1996 Impala SS
2000-2005 Impala
1997-2005 Malibu Classic
1997-2003 Malibu
1986-1993 Allante
1982-1996 Fleetwood
1985-1996 Fleetwood Brougham
1992-2004 Seville
1992-2004 SLS/STS
1985-1999 Deville
1994-1999 Deville Concours
1997-1999 Deville D'Elegance
1988-2002 ElDorado
1994-2002 ElDorado Touring
1999-2007 Escalade
2000 LS/LS1/LS2/LW1/LW2
2001-2002 L100/LW100
2001-2003 L200/LW200
2001-2005 L300/LW300
2004-2005 L-Series
2002-2008 VUE
1996-2002 SL/SL1/SL2
1996-2002 SC1/SC2
1996-2002 SW1/SW2

Posted on Feb 23, 2011

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I have a 2007 Buick LaCrosse we have changed the transmission and after installation of the transmission the engine will only start for a few seconds then go dead then you have the message illuminated that...

Checking the data line the scan tool use to communicate with the PCM would be the first thing to do . Do you know what a class 2 serial data communication network is ? Is there B+ voltage at pin #16 at the DLC ? If you had a professional type scan tool that could communicate with all modules on the vehicle you probably would find a U code stored in one of the other modules ,this would point you in the right diagnostic direction . It won't stay running because the PCM is not able to read the fuel enable message from the BCM or the theft module . Which ever controls the anti-theft system .
012 GM Class II Communications

Do you have wiring diagrams to check the circuits with ?

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Is there a way to check the computer module on a 2003 Buick rendezvoous

Check it for what ? Hooking up a scan tool is the best way , checking DTC'S - diagnostic trouble codes ! If it shows no communication on the scan tool that's when you start testing power an grounds . Other then that you can't do anything . Only the factory know's what software is programmed into it !
ECM Inputs and Outputs Diagnosis

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Is the tps sensor on a 05 Buick LaCrosse CXL 3.8L serviceable?

define serviceable? Is your vehicle electronic throttle controlled ? Do you know what that is ? Do you have a DTC - diagnostic trouble code ? There are two sensors in the throttle body an two in the gas pedal too. Chevy GMC Code P2135 TPS Problems

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How to fix 2010 Buick Lacrosse stabilitrak?

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I replaced the transmission in a 2006 buick lucerne. no problem until I went to start the car . no start no communicaion with computer

Quite likely the on-board ECM needs telling the transmission has been changed or there is a fault in the new transmission.

It probably needs dedicated diagnostic equipment.

Feb 28, 2015 | 2006 Buick Lucerne

2 Answers

What can I do when I got code u2105 in my car (Opel Astra 1600)

year, country?
this is covered in the factory service manual, "FSM".
for each code , there is a page, that tells you/ mech.
what the test is, what it does, how to do sub tests to isolate true cause.
my guess is the U code is in the cluster display?
best is to get a full scan of the car, OBD2 (EOBD?) to see all errors, all DTC. errors. then have all the facts, on errors.
lots of opel,, my guess 2007?
CAN Bus Error ECM
best i can do (no cars here usa) is above. google searching in Germany.
the car has many computer modules and one can not
communicate to the ecm(ECU/PCM) OR BCM.
is the car battery low>?
check all fuses. in car, in all fuse boxes, test them.

this is the best i can do ,no books on opel here.

Jan 03, 2015 | 2007 Opel Astra 1.6

1 Answer

Code u2100- u2105

U2100 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Off (4L30-E Transmission) Conditions
Cause Key on and the TCM detected a loss of communication on either Communication Area Network (CAN) Bus line for one second

U2103 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Reset Counter Overrun (4L30-E Transmission)
Cause Key on and then the TCM detected a loss of communication on either CAN Bus line that exceeded 40 time out requirements

U2104 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Reset Counter Overrun (4L30-E Transmission)
Cause Key on and then the TCM detected a loss of communication on either CAN Bus line that exceeded 40 time out requirements
U2105 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Error ECM (4L30-E Transmission) Conditions
Cause Key on and the TCM did not receive ECM messages for 1 second

or you can ask the 24 hrs live technical support was multi-diag, they will like to help you, good luck

Aug 14, 2013 | 2005 Isuzu Ascender

1 Answer

What is code B2799

This Diagnostic Trouble Code (DTC) is output when the Engine Control Module (ECM) detects errors in communication between the Transponder Key Electronic Control Unit (ECU) assembly and the ECM, or in the communication lines. This DTC is also output when an engine start is attempted while the ECU communication ID between the transponder key ECU assembly and the ECM is different.
Possible causes Faulty Key Faulty transponder key amplifier Faulty Transponder Key Electronic Control Unit (ECU) Transponder key amplifier wire harness Faulty Engine Control Module (ECM)

Mar 02, 2013 | 2007 Lexus ES 350

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