2017 Lacrosse Premium - Electrical Hiccups

[MCBuick24]

In case anyone needs this information, I finally narrowed the issue down to the "serial gateway module" this module acts like a router for the other modules so it plays a big part in communications, I replaced the part myself $57.00 the problem is you have to disassemble a lot of the dash to replace this part it sits behind the radio ! I took the car to the Buick dealership and had it programmed for $99.00 the car has run flawless for a month now I believe this time its fixed for good 👍

Just curious if your LaCrosse is still fixed after you replaced the serial gateway module? My 2018 LaCrosse is doing the same thing and already did new wheel bearings, gas pedal position sensor and reflashed the power steering module at the local Buick dealer but problem still persists. My local Buick service manager who worked as a mechanic for the dealership doesn't think there's a high probability that will correct my car's problem. They want to replace the rack and pinion because they believe the power steering control module (which is built into the rack and pinion) is defective. Appreciate any help

 

[MDC58]

Just curious if your LaCrosse is still fixed after you replaced the serial gateway module? My 2018 LaCrosse is doing the same thing and already did new wheel bearings, gas pedal position sensor and reflashed the power steering module at the local Buick dealer but problem still persists. My local Buick service manager who worked as a mechanic for the dealership doesn't think there's a high probability that will correct my car's problem. They want to replace the rack and pinion because they believe the power steering control module (which is built into the rack and pinion) is defective. Appreciate any help

No that did not fix the issue, after about a week all the symptoms came back so I took it to the dealer and they thought it was related to the steering rack because the wiring diagram shows the wires passing through that part, after having the car for almost two months at their shop they narrowed it down to the shift control module and the electronic gear selector they are waiting on the new gear selector, I will keep you posted.

 

[jeffbazell1]

Hopefully you found the issue. One frustrating thing about this car (and most GM vehicles) is their lousy wiring. So many important wire connectors and harnesses are exposed to the elements, get wet, dirty and corroded. Next time you're driving down a road, note how many GM (mostly Chevys) have a Daytime Running Light burnt out. Ugh!

 

[RD_Atlanta]

[Quick edit: Corrected a couple of sloppy typos]
I had to read FelixUnger's original post a couple of times. It's strange that OEM testing did not find that this type of vehicle behavior can happen and designed fail-safe's so that the vehicle cannot behave this way. Hopefully the Buick executive's monitoring this forum will take note. It sort of reminds me of the classic line by Dan Akroyd in 'Driving Miss Daisy' when Boolie Werthan said "Mama, cars do not behave, they're behaved upon". Or that's the way it should be 🙂.

 

[G-696357]

Did you get your 2017 buick lacrosse fixed

 

[MDC58]

Did you get your 2017 buick lacrosse fixed

Not yet it's been at the dealership for almost 3 months now, one of their techs narrowed it down to a issue ( he thought) to the shift control module but he quit and went to work for another dealership, they have now promised me that they are going to put their top mechanic with 29 years experience on it he he can figure it out they will have a engineer from Detroit fly down and look at it I told them there are other people on a Buick Forum with the exact same issue, hopefully it will get resolved.

 

[MDC58]

Did you get your 2017 buick lacrosse fixed

Not yet it's been at the dealership for almost 3 months now, one of their techs narrowed it down to a issue ( he thought) to the shift control module but he quit and went to work for another dealership, they have now promised me that they are going to put their top mechanic with 29 years experience on it he he can figure it out they will have a engineer from Detroit fly down and look at it I told them there are other people on a Buick Forum with the exact same issue, hopefully it will get resolved

 

[MCBuick24]

What's strange is this seems to be a problem with the LaCrosse Premium models since that's what we all have. Can't belive they had the car for 2 months. My local Buick dealer wants to replace the rack and pinion and being an AWD it's quite the job and close to $3k to boot. After having it that long did replacing shift control module curious if the symptoms are still presen?

 

[MDC58]

What's strange is this seems to be a problem with the LaCrosse Premium models since that's what we all have. Can't belive they had the car for 2 months. My local Buick dealer wants to replace the rack and pinion and being an AWD it's quite the job and close to $3k to boot. After having it that long did replacing shift control module curious if the symptoms are still presen?

They haven't replaced it yet, it's still sitting on the front seat of the car, my guess it's related to the immobilizer system in the car when I put brought this up at the dealership they all went hmmm never thought of that, you are correct this looks like a issue they have had all along, I will keep you posted if there top mechanic can't fix it maybe the engineer from Detroit can 🙏

 

[MDC58]

They haven't replaced it yet, it's still sitting on the front seat of the car, my guess it's related to the immobilizer system in the car when I put brought this up at the dealership they all went hmmm never thought of that, you are correct this looks like a issue they have had all along, I will keep you posted if there top mechanic can't fix it maybe the engineer from Detroit can 🙏

Update ! The dealer called me yesterday and said my car was ready for pick up 😁 Their top mechanic said he thinks it was a communication issue between the shift control module and the gear selector, so they replaced the gear shift selector and installed the shift control module I dropped off to them 3 months ago lol, they reprogrammed everything with updated software and gave the car back me so far "no issues" I will keep you all posted. The dealer charged me "nothing" service manager said they were very sorry it took 3 months to get the car back to me because of this the owner said "No Charge" 👍

 

[MCBuick24]

Update ! The dealer called me yesterday and said my car was ready for pick up 😁 Their top mechanic said he thinks it was a communication issue between the shift control module and the gear selector, so they replaced the gear shift selector and installed the shift control module I dropped off to them 3 months ago lol, they reprogrammed everything with updated software and gave the car back me so far "no issues" I will keep you all posted. The dealer charged me "nothing" service manager said they were very sorry it took 3 months to get the car back to me because of this the owner said "No Charge" 👍

That is awesome news and pretty generous of the Buick service center who are not known for giving customers very many breaks like that. I sure hope that solves your problems with you car and I'm hopeful it might be the solution for my LaCrosse as well. Any chance you might be willing to send the portion of the paperwork that shows the parts and service they performed so I can show that to my local Buick service advisor hoping they will replace these parts for me as well and once and for all solve this years long issue with a car I otherwise love driving. Thanks again for the update.

 

[MDC58]

That is awesome news and pretty generous of the Buick service center who are not known for giving customers very many breaks like that. I sure hope that solves your problems with you car and I'm hopeful it might be the solution for my LaCrosse as well. Any chance you might be willing to send the portion of the paperwork that shows the parts and service they performed so I can show that to my local Buick service advisor hoping they will replace these parts for me as well and once and for all solve this years long issue with a car I otherwise love driving. Thanks again for the update.

Thank you, I hope it solves the issues as well I would be glad to share the parts list but they gave me no invoice just handled me my keys back, I think it was the "Shift Control Module" that finally corrected the issue the reason I say that the mechanic showed me the wiring diagram and said the gear selector connects directly to the that part of that part was defective it could cause all types of communication issues, I will keep you posted please share this information with your dealership.