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Shift to Park

18K views 51 replies 16 participants last post by  divotdug 
#1 ·
I have a 2018 Acadia SLT. It has had an ongoing issue with not recognizing when the vehicle is in PARK-I get a notification saying "Shift to Park" with the slightly annoying "ding! ding! ding!" that will not go off. I fidget with the gear, sometimes that works, while other times I start it, change the gears and slowly put it back in PARK...sometimes that works, while other times it does not. I have had it into the shop (GMC Certified) twice-which both times coded the switch, which is again being replaced, as I type! Anyone know of this happening commonly or did I just get a dud? If so, what was done. Nowadays, as you all know-if it doesn't code "there's nothing wrong"...frustrated with this plug and play world! I miss the days of REAL mechanics! But then, everything is electronic...ugh
 
#2 ·
A common issue apparently on several models.

If you are handy . .. there is a way to replace just the switch and modify it for potentially better results. But not covered by warranty.

There is a TSB from GM and a new shifter and switch repair on this.

Read the following thread and download the included pdf document.

Shift to Park problem
 

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#4 · (Edited)
That is what the TSB indicates. They install P/N 84955381 for Acadia and some other.
The linked thread contains the info as well as the included TSB on pdf download.
Also another thread regarding the over travel that is the root cause of the failed micro switch.
Several here, like the OP, have had the shifter replaced and the issue returns eventually. Unless the switch specification was improved.

There is also a simple mod to the micro switch lever that may resolve the over travel stress to the micro switch.

Picture below of the new micro switch harness and park interlock solenoid - - -

Circuit component Automotive lighting Electrical wiring Gas Cable
- - Click To Enlarge Photo - -
 
#5 ·
My understanding the shifter was upgraded. That is the one we got.

GM went to the switch and harness to make th3 fix faster and cheaper vs replacing the shifter.

As I have read the switch is not getting a good reading from the BCM and it causes it not to read the shifter position and gives it a false reading. The new parts are tune to better read the signal.

Ours failed a year in and the fix has lasted 2 years so I assume the new switch in the shifter worked. Twos who got the early shifter replacements do report second failures.

Keep in mind this was based on responses on the web as to who it worked for and who it did not work for.

Also note this was not just the Acadia as a number of other models had sporadic failures.
 
#6 · (Edited)
Yes. . well aware of all of that and how this shifter is used in other models as well as similar shifters that have the same micro switch issue. It's all in a the newer TSB as well as a previous one with the lame. . "flick the switch 50 times" recommendation. :rolleyes:

However. . . the shifter had several part number revisions in the past year or two.
Have been following this issue since early 2019.
Also, the work and time installing the switch and harness will be about the same as was installing a new shifter. Plus the time to remove the original wiring and installing the new. Whereas before, it was just pulling the entire shifter out and installing a new one. In both cases. . the console needs to be pulled back and shifter removed.

I have both the new harness and a spare shifter. I've posted pictures in another thread .
Our Acadia has not had the issue as of yet.

I and others have been in contact with Omron. . . the micro switch maker and the issue is over travel stress.
Also, the shifter is GM spec'd but of course, supplied by a vendor.
 
#7 ·
Well who would have known the my 2017 (bought last May) would have a shift to park issue? The DEALERSHIP! That’s who! I’m so mad they sold me that car knowing full well of its issue. Before buying the car, When I researched Acadias I didn’t see anything about it. Well supposedly, when I took it a month ago to have the issue fix at the dealership, the guy told me GM has a new shifter, etc to fix this! Great I thought, until 2 weeks after I get the car back and it’s doing it again. So they are going to have to fix it again. I could do this all day, but my warranty runs out next month. Then I’ll have to pay to have it fixed every month! GM SUCKS! Has anyone had it repaired and it fix the problem indefinitely?
 
#8 · (Edited)
Hello and welcome. . . . I guess.
Many have had the repair and some return while others are fine.
If your problem was not fixed it doesn't sound like they did the correct fix. You should ask what exactly was done with the warranty repair invoice that lists parts and labor on your personal copy.
The shift to park message/issue has been an occurrence for many owners. There are several threads here about it and had you researched here before buying it would have come up.
Read a few of the threads . .
Shift to Park

Tested working, 2017 shift to park fix.

Search results for query: Shift to park solved

Neither here nor there. The problem is a small switch in the upper shifter assembly that signal the shift lever is in the Park position.
GM used to replace the whole shifter. Now there is a wiring harness with the switch that they should have replaced.

IMO and others, the issue is pretty simple repair and the Shift To Park error occurs on several models and brands like Ford and similar problem with other brands as well.

Ford Shift to Park - Google Search
 
#10 ·
Thanks, agreed had I known this forum existed I would have been aware prior to purchase. Still think the dealer should have disclosed this info.
Anyway, I’ll look at the invoice and see exactly what was done. I’m sure it was a new shifter and harness. But will mention this thread with hopes they get it right this time.
Thanks against.
 
#9 ·
I had the issue repaired on my '18 in November of 2019. At that time the TSB called for a wiring harness change.

Issue returned in December 2019. At that time the dealer replaced the shifter assembly. So far no additional issue.

The TSB for this issue has been revised several times. Make sure your service advisor is aware it was revised December 2020.

While a common failure, it does not fail on every vehicle. selling dealer has no way to do predict if it will fail on any given vehicle. That is why vehicles come with a warranty.
 
#13 ·
I had the issue repaired on my '18 in November of 2019. At that time the TSB called for a wiring harness change.

Issue returned in December 2019. At that time the dealer replaced the shifter assembly. So far no additional issue.

The TSB for this issue has been revised several times. Make sure your service advisor is aware it was revised December 2020.

While a common failure, it does not fail on every vehicle. selling dealer has no way to do predict if it will fail on any given vehicle. That is why vehicles come with a warranty.
Thanks, service manager said it was revised part released Feb of this year. I’ll look up the part number and see what I come up with.
 
#16 ·
Thank you this is helpful. My next question would be why do t I consistently get the error?

also, the part(numbers) they used are
84955381 Switch
84955380 cover
84733196 harness

I’ll try to look up the pdf from laptop, I’m only on my phone, maybe that’s why it isn’t working for me.
 
#17 ·
Those part numbers look correct from what the TSB states.
As I said earlier in the thread. . . I am guessing you are getting the error because perhaps the tech may have damaged the switch or caused a now loose connection when it was repaired. Can you turn the engine off ?
 
#28 · (Edited)
The thing is. . If you read the TSB . . . in order to do the latest fix with the micro switch/wire harness . . . the whole shifter has to come out.
Maybe the dealer is electing to just replace the shifter rather than take the shifter out, unfasten and pull out the original micro switch and wiring harness (plus the Park interlock solenoid) which is part of it.
IMO .. . the new TSB repair is more time consuming than just replacing the whole shifter. GM should perhaps have dealers send the shifter core back to have the new parts retro fitted at a facility.

Disconnecting, unclipping the 2 connectors from the shifter, carefully undoing the wire harness and fishing the new wires back into the proper place requires some dexterity.
If a tech with bratwurst size fingers has to do it . . . . good luck.

Here is the part(s) that needs to be removed for the latest TSB. . . harness with switch and solenoid.

Click On Picture to See Full Size.
Circuit component Electrical wiring Gas Automotive lighting Electricity
 
#29 ·
IMO .. . the new TSB repair is more time consuming than just replacing the whole shifter. GM should perhaps have dealers send the shifter core back to have the new parts retro fitted at a facility.
Without a doubt more time consuming.

Prior versions of the TSB paid .6 hours of labor for the repair on an Acadia. The latest version pays 1.4 hours.

IMO, unless the shifter has been modified, swapping shifters does nothing but kick the can down the road for another 20k miles.
 
#33 ·
I believe there were a couple of revisions to that TSB in 2021, none the less, it is not something covered by the power train warranty.

Unless you have a friend or family that is a service advisor, I doubt it is something that will be covered just because one walks into the service center with a TSB in hand.

TSB's are a tool for the tech, not for customers to negotiate free repairs.
 
#34 · (Edited)
Unless you have a friend or family that is a service advisor, I doubt it is something that will be covered just because one walks into the service center with a TSB in hand.
It's doubtful a friend or family member would risk their job on a non-warranty repair that's performed under the guise of a covered repair. That's the best way I know to get the shop back-flagged during a warranty audit.
 
#39 · (Edited by Moderator)
3 times not fixed = lemon in Georgia. The warranty is on the new part, not the faulty one. Just holler if you me.😉
Mine just started with this issue. My daughter's 2018 did this and after several trips to dealers she traded it for a 2019 which was supposed to not have the problem. Her 2019 is now doing it and my 2019 at 51K just started doing it. Just found this video and I say it is worth a try.

gmc acadia shift to park fix - Bing video
 
#41 · (Edited)
Mine just started with this issue. My daughter's 2018 did this and after several trips to dealers she traded it for a 2019 which was supposed to not have the problem. Her 2019 is now doing it and my 2019 at 51K just started doing it. Just found this video and I say it is worth a try.

gmc acadia shift to park fix - Bing video
Read this thread linked below.
Tested working, 2017 shift to park fix.
It contains all the info about the cause of the issue and how to fix it or even just bypass it.
The micro switch that causes the issue is over stressed but can be replaced if you are a bit handy.
Take the time to read it all and learn instead of looking for some "quick fix".
 
#42 ·
Hi All - I have a 2017 GMC Acadia, and this behavior started happening last year when I had an issue with the battery; and unfortunately the warranty had run out by the time it started. One thing that I've noticed which makes the behavior worse is when the vehicle has been washed. It will fail to recognize being in park more frequently for a few days after the car wash.

There is a class action lawsuit specific to the Acadia:

I called the dealership today to see what the cost would be. I told him I have the TSB in hand, and that it's .6 hours + plus the cost of the harness. All he would say is that it's $179 for an "inspection", and then they'll discuss whatever they find wrong with the vehicle. :mad:
 
#43 · (Edited)
... All he would say is that it's $179 for an "inspection", and then they'll discuss whatever they find wrong with the vehicle.
What else should they say if it's possible other things may cause the condition?:unsure: No one here has discussed a car wash correlation to the problem.
 
#47 ·
I worked on my Shift to Park error today. At 60,000 miles, this is the second time it’s happening; first time entire shifter was replaced by dealer.

I decided to only replace the switch. I also chose to use the GM switch which comes with some wiring and a solenoid under part 84955381. $20 plus shipping online.

I cut off the switch so I didn’t have to replace everything else (much more work). I was able to pop the sides off the console, remove 10 x 10mm bolts, slide console back a few inches, remove the rubber and then plastic trim plate just below USB ports, lift that front edge out of clip, and gain just enough access by lifting to not disconnect all of the various switch connectors. (I posted a much more thorough description of this process last year / search for buzz or rattle shifter).

Although desoldering the old switch and soldering In the new one would have been simple enough, I didn’t feel like sucking fumes today. :). So instead I cut the wires to the old switch close to the switch. Cut the wires to the new switch leaving about 3” leads. Stripped both ends and crimped them together with butte connectors. Wrapped felt tape around the butte connectors just to prevent tapping or rattle against anything inside there. There’s PLENTY of room to use any type of connector you’d want.

Work slow, work gentle, and it’s easy.
I did put a bend into the new switch as JayTee recommended- hopefully that prevents having to fix this a THIRD time in the future.
 
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#48 ·
Thanks for this feedback !
Excellent idea buying the harness and just using the switch. I too have one handy since it's cheap insurance. Also, several Omron switches from the same class as the factory one.
Hoping the repair is the last that has to be done due to the switch. Let us know if not. . .
The only other thing I've read is a pivot pin in the upper shift lever handle sometimes slides out of place and causes a similar issue.
But at least both are repairable without major expense if a person is handy.
 
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#49 ·
It appears the original case " Napoli-Bosse et al. v. General Motors LLC" was dismissed, however; there are still on-going cases...

One good thing did come out of this court case. The "cause" has been identified. See section "50" below for details.

The parties also dispute how many vehicles were affected by this issue. See, e.g., ECF No. 89-1 at 3-4. But it is undisputed that at least some 2017-2018 GMC Acadia vehicles “contain shifter assemblies that fail to recognize that the vehicles have been placed in park, erroneously direct the driver to ‘Shift to Park,’ and prevent the vehicle from turning off.” ECF
No. 89-1 at ¶ 8. Plaintiff’s expert Darren Manzari opined that “[o]ver one hundred thousand [vehicles] have experienced a defect whereby a ‘Shift to Park’ message appears on the vehicle’s instrument cluster directing the driver to shift their [sic] vehicle to park despite the [fact that the] vehicle is already in park.” ECF No. 92-1 at ¶ 28. 7 After launching an investigation into the shift-to-park defect in August 2017, ECF No. 89-1 at ¶ 56, GM was able to confirm the cause of the issue in August 2018. ECF No. 89-1 at ¶

****
50. The parties agree that the shift-to-park issue is the result of a defect whereby silicon dioxide or glass (“SIO”) builds up on the park switch contacts in the Class Vehicles’ shifter assemblies, which causes the Class Vehicles to fail to recognize when their transmissions have been placed in the park position and prevents the vehicles shutting off. SIO or glass builds up over time because ‘[t]he park switch has organic silicon within the switch at some point. And through the actions of the
switch opening and closing, that organic silicon is decomposed into its base elements and the organic silicon will immediately reform in the presence of heat into silicon dioxides and attach itself to the surfaces of the switch contacts.’


Now we wait for the next Technical Bulletin to be published with the correct fix for the issue.

For any of you who are also experience intermittent issues with your key fob - that bulletin number is 16-NA-396. Intermittent Operation of Key Fob, Door Unlock Inoperative, "No Remote Detected", message with possible TPM MIL.

Good luck!
 
#50 ·
Looks and sound like an attempt to *Spam*people to get on board a law suit.

Also. . .. I highly doubt and would need to see proof of SIO2 building up on the micro switch contacts.
IE - - " because ‘[t]he park switch has organic silicon within the switch at some point. "

"At some point . .?" the switch had "organic silicon" inside the switch? How. . .? From where? Why?


After close inspection and study, the more plausible cause is exposing the switch lever and internal mechanism to excessive over travel and causing eventual internal damage to the "snap action" design of the switch.
 
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#51 ·
Hi JayTee,

Not sure if I'm reading your message right - I have no feelings one way or another if anyone else considers a lawsuit either of their own making, or to join one of the existing ones. My intent is to share information that is specific to this very issue. The first class-action was dismissed, and the information above, I copied directly from the final decision documents. (Link is above for review).

GM identified Silicon Dioxide to be the cause - again, all of this is in the final decision document referenced at the link above. As these documents are filed with the court, I am assuming GM to be on their best behavior and not lying about the solution. Especially knowing that any of this material could be used against them for any other legal purposes.

**Granted, the technical bulletin information regarding the key fob, was again information to share to the group for those who have also experienced this issue as well. I have experienced both these issues myself, and there were some comments about what was causing the problem, and the fact the dealerships don't seem to be hitting the mark on resolving either of these issues.
 
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