GMC Acadia Forum banner

1 - 20 of 30 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #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
 

·
Registered
Joined
·
2,044 Posts
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
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
 

Attachments

·
Registered
Joined
·
134 Posts
we had the issue but they replaced the shifter and no more issues. They now just do the sensors and harness.
 

·
Registered
Joined
·
2,044 Posts
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 - - -

Shifter Micro Switch Harness and Interlock Solenoid.jpg - - Click To Enlarge Photo - -
 

·
Registered
Joined
·
134 Posts
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.
 

·
Registered
Joined
·
2,044 Posts
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.
 

·
Registered
Joined
·
7 Posts
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?
 

·
Registered
Joined
·
2,044 Posts
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
 

·
Registered
Joined
·
3,146 Posts
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.
 

·
Registered
Joined
·
7 Posts
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
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.
 

·
Registered
Joined
·
7 Posts
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.
Again!
 

·
Registered
Joined
·
7 Posts
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.
 

·
Registered
Joined
·
2,044 Posts
Thanks but pdf didn’t work though.
As long as they have the 19-NZ-206 TSB number they can look it up. The pdf works on my laptop.

If they used the recommended parts for your repair. .. I'm wondering if whoever did it damaged the very delicate switch when it was installed. This kind of repair should be done only by someone careful and skilled in delicate electrical repair. The small Omron micro switch should also be adjusted in my opinion, so that it is not stressed by over travel. Omron is the company that makes this switch.

Here is the real root cause of of this Shift To Park issue: - - -

See this GIF that illustrates an adjusted micro switch to reduce over travel on its lever. Essentially, a horzontal plunger/stud on the side of the shifter stalk, applies upward movement and pressure onto the micro switch lever. The throw on that plunger/stud presses the switch lever much more than needed to operate the switches own internal "snap action".

Also below, is a picture of the micro switch as it comes before being installed in the shifter. Note the distance it has between its lever and the black portion in the center of the "blue" activation button on the switch body.
The lever only needs to press on the black center of that button about 1 mm to trigger the switches spring loaded internal snap action.

The micro switch lever only triggers and releases the internal snap action of the micro switch . . . excessive movement smashing down onto the blue button of the switch only stresses the internal release of the switch.

In the shifter as it was designed, the switch lever is being smashed upward into the switch body with excessive force or "over travel" which exceeds the Omron micro switch specifications.
By bending the switch lever upward as shown in the GIF. . . it allows enough movement to trip the snap action of the switch without over travel stress and eventual damage.
Think of the switch internal snap action as a "trigger" by only a small amount of movement by the lever.

Note: . . . Putting an upward bend in an existing micro switch lever may not remedy the issue if it has already been stressed by over travel. In my opinion. . any time this micro switch it replaced by a repair action, it should first have a slight upward bend in the lever before being installed to prevent this over travel from happening again.

10769
Switch GIF.gif IMG_20210311_122114757.jpg
 

·
Registered
Joined
·
7 Posts
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.
 

·
Registered
Joined
·
2,044 Posts
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.
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 ?
 

·
Registered
Joined
·
7 Posts
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 ?
The engine turns off, but the power is still on.
 

·
Registered
Joined
·
89 Posts
Mines been repaired and the new shifter has been good for a long time now. Give it one more chance.
 

·
Registered
Joined
·
4 Posts
I have a 2017 GMC Acadia. Had the same problem for the second time (first was a couple of years ago). This time they replaced the switch, harness and cover. It works fine now.
 
1 - 20 of 30 Posts
Top