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Steering Assist is Reduced Drive with Care

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#1 ·
I have a 2018 Acadia Denali & it is showing the Steering Assist Error Message which I believe is something with the Thermostat. Can someone please quickly explain the cause of this problem & what the Solution is? I want to be able to present it to the dealer if they try and tell me the problem I'm having is something else.


Thank you,

Dan
 
#2 · (Edited by Moderator)
#13 ·
Read through these two threads: Electric power steering assist warning and 2017 Acadia, " Steering Assist Reduced Drive with care" message. There may be others linked inside the discussion or available to you if you search the forum with keywords "Steering Assist Reduced." Be sure the threads you read are about the 2017+ model years with electric power steering. Good luck at the dealership.
Took to dealership. Advisor indicated thermostat needed replacement. $1400.
 
#3 ·
I have a 2018 Acadia Denali & it is showing the Steering Assist Error Message which I believe is something with the Thermostat. Can someone please quickly explain the cause of this problem & what the Solution is? I want to be able to present it to the dealer if they try and tell me the problem I'm having is something else.


Thank you,

Dan
I am having this issue now with my 2019 Acadia. Were you able to get the issue resolved?
 
#4 ·
Had the same problem back in June and before message would come on then go off then it came on consistently air conditioner shut down. Research the issue tried a few fixes the one I found at work or my problem was the battery terminals need to be cleaned and tightened. Once that was done the problem was fixed so far the last three months have been good.
 
#9 ·
I have a 2018 Acadia Denali & it is showing the Steering Assist Error Message which I believe is something with the Thermostat. Can someone please quickly explain the cause of this problem & what the Solution is? I want to be able to present it to the dealer if they try and tell me the problem I'm having is something else.


Thank you,

Dan
I just saw this same message come up on my 2017 Acadia this morning. I was wondering what this problem was. I went to start up my truck this evening and no messages on the dashboard. This had me puzzled as here it is the week of Thanksgiving and we are scheduled to hit the road later this week. Trying to get into the dealership and of course no available appointments.
 
#10 ·
I have a 2020 and experienced this twice but I was wondering if anybody has had other issues while the message was up. I had several other issues as well.
Auto Start stops working
Check Engine light blinks
Strange Noise from Engine
Engine runs rough
Emergency brake sets when in park
Has anybody seen this?

I tried to stop at the local GMC dealership while this was happening and was told I needed an appointment but he did check for error codes and there were none, The second time it happened stop at auto parts store again no error codes. I did keep the engine running both times. very frustrating
Thanks
Wnova
 
#16 ·
Having same issue with steering assist reduced & no temp indication.

Already replaced temp sending unit.
Some confuse temp. sending unit with thermostat. They are in same area location. I bought a thermostat & tube, but was able to just replace the sending unit without pulling the thermostat tube out of the way so they are still in the box.

I don't suspect the thermostat because the engine is cooling, although an air pocket around the sending unit from coolant not circulating is plausible. This would give a low reading, but not no reading at all?

I have checked the sending unit wiring all the way to the computer & reseated plugs.

When I disconnect the battery for 15 minutes, all is well again. The battery connections are all good & battery is only a couple years old (this means nothing nowadays).

I'd like to hear feedback from people who have corrected this issue, but a year or so down the road. Not within a week of replacing or correcting something when it could pop back up a month down the road. Not a lot of info on this.

These vehicles are prone to computer glitch's and need reset way to often, (not as often as my CTS) could this be the case with this issue???
 
#23 ·
Having issues with my 2018 Acadia. Steering assist warning coming on then the AC quits on me In the heat of Florida. Next my engine light comes on. I have no issues with the steering getting hard or difficult to drive. So I’m pretty sure it’s has to be a issue of some kind with something else.
but what I’m seeing here is this issue has been happening in almost all years of this SUV. Why has there not been a recall on this.
when we bought this vehicle we were never offered a extended warranty. Our local dealership said we can still get one. It is going to run us $4000 for the warranty. But reading all the issues every One is having.Along with all the past issues we have had makes me think it will be worth it.
my husband keeps resetting the car by disconnecting the battery each time the warning comes on and the AC quits. And it solved the problem for a day or so. The warranty will be good for 4 years. Does anyone else have a extend warranty and do you feel it has been worth the expense. We are 2 months out of our 60,000 mile warranty. So no more warranty left on our car. And reading the price the one person said they charged him to replace his thermostat tells me it might be a good move.
 
#25 ·
I know exactly what you’re saying. We have a multiple in our car and he’s changed his day to come here because the warning is up and then when he gets here and he turns the engine overthe warning light is gone
. I’ve been disconnecting a battery and hooking it back up after about 10 min,and when we turn it over it seems to solve the problem temporary I’ve been reading a lot and a lot of people are changing thermostat and that seem to be responding to the problem so that’s the next thing we will be doing
 
#26 ·
I have a 2018 Acadia Denali & it is showing the Steering Assist Error Message which I believe is something with the Thermostat. Can someone please quickly explain the cause of this problem & what the Solution is? I want to be able to present it to the dealer if they try and tell me the problem I'm having is something else. Thank you, Dan
i had the same problem and it is the thermostat
 
#27 ·
Can’t believe that was it! 2019 Acadia SLT2 and exact same problem out of nowhere: “Steering Assist is Reduced Drive with Care”, and at the same time the AC started blowing with no cold air at all- (it went to full power without touching it.) Cleaned the terminals, including fuse terminals on top of battery. Waited 15 mins and everything worked perfectly fine.
 
#32 ·
The cause is that the thermostats are opening too early and allowing the engine to not warm up to proper operating temp - this causes the control module to suspect that the coolant temp sensor is inaccurate and there for reduces stress on the coolant system and other sub systems by turning cooling fans on high, and reducing electrical draw by offering less electric steering assist - it won't always set a hard code, but will always have a "pending" status codes for p0128 - clear the codes and everything goes back to normal until the conditions are met to set the code again - we have replaced a few of these thermostats in the last couple months on the LGX high feature 3.6 - In our market/region, going rate for that job is about $1100 out the door.
 
#34 ·
I have been having the same issue since March 2022. It cleared on its own for about six months, then it came back. I changed the battery and it was fine for about two months. I have been disconnecting the battery and it is fine for a few hours, days, or weeks, but I can't figure out what is triggering this problem. I finally gave in and took it to our local mechanic to get a new thermostat and sensor put in. Initially quoted $1,100, but they just called saying they recommended changing some seals and a fuel pipe in the process of putting everything back together, which will be an additional $300. I hope this solves it, or I am going to be a pissed off puppy! The fact that this is such a common issue and GMC has not come out with a formal recall is ridiculous. I am keeping all my receipts in case they do ever recognize their mistake and I can claim a refund.
 
#35 · (Edited)
Hi All,

I have same issue on my 2017 Acadia Denali , current odometer 112,891 kms / 70,147 miles.
Took it to local GMC Dealer Service centre. They are saying is a "big" job with 6 hours of work required.
They are saying the "Thermostat is stuck" and is blocking the engine coolant from flowing correctly through engine.
And due to the location of thermostat box, it will require them 6 hours to replace and they will also need to flush out and refill engine coolant. They mentioned that I was lucky that I didn't drive a lot with this condition as there was possibility of engine overheating and possibly blowing up.

Wanted to check if C$2250.00 + tax , seems genuine for this job?
I am reading folks talking about $1400 out-the-door, thats like $1866 CAD.
This is GMC dealership located in Metro Vancouver, CANADA.

Is it valid explanation that engine could overheat due to this issue?
I read through this thread and no where anyone has talked about engine overheating. I took my car to dealership right after warning message came, so not sure if engine is heating due to this.
 
#36 ·
Hi All,

I have same issue on my 2017 Acadia Denali , current odometer 112,891 kms / 70,147 miles.
Took it to local GMC Dealer Service centre. They are saying is a "big" job with 6 hours of work required.
They are saying the "Thermostat is stuck" and is blocking the engine coolant from flowing correctly through engine.
And due to the location of thermostat box, it will require them 6 hours to replace and they will also need to flush out and refill engine coolant. They mentioned that I was lucky that I didn't drive a lot with this condition as there was possibility of engine overheating and possibly blowing up.

Wanted to check if C$2250.00 + tax , seems genuine for this job?
I am reading folks talking about $1400 out-the-door, thats like $1866 CAD.
This is GMC dealership located in Coquitlam, BC, CANADA.

Is it valid explanation that engine could overheat due to this issue?
I read through this thread and no where anyone has talked about engine overheating. I took my car to dealership right after warning message came, so not sure if engine is heating due to this.
Generally, this condition occurs because the thermostat may stick - - -OPEN . .. . so the engine control computer see it as not getting to a warm enough temperature in a certain amount of time.
You can reset this error by disconnecting the negative battery cable waiting a minute and connecting it back up. Or. .have someone with a shop reset it with a device that plugs into the Acadia under the dash.
Some also think it is just an electrical glitch since the coolant temperature is correct, and the engine computer interprets it as incorrect. . . . witch causes the messages you are seeing.
 
#38 ·
Add mine to the list. 2017 with 58k on it. I tried the battery terminals and it worked for a month. Now I guess I'm tearing this thing apart to replace the themostat and temp sensor.


Mine just randomly started with EVAP codes too. I had planned to drive this thing for a long time but it's getting irritating with issues under 60k miles.
 
#39 ·
Okay, my 2017 Acadia just started giving me the same message. Driving assist reduced…blah,blah,blah. So I googled everything I could find about it. Then tried cleaning the battery terminal and , weirdest thing, it all started working fine. I’m not sure if it will continue working. But at least for now it looks good. Hmm?
 
#40 ·
Wife’s 2017 Acadia Denali ( 34,000 miles ) has had this issue for the last 8 months. It first came on while we were on the freeway for about 45 min. Cool temp gage drops to cold, AC blows Luke warm and steering asist doesn’t work, fan kicks on high.Cleaning the terminals and disconnecting the negative one for about 5 minutes has been resetting the issue and clearing the code. my wife drives less than 10 miles to work and very rarely makes her way on the freeway, so for that reason the message rarely comes on. What my wife has noticed it comes on after about 45 minutes of freeway driving, When she has to drive to clients out of town. Called local GMC dealer and they are recomending replacing the thermostate housing but first to bring it in the next time the message comes on to check the code being thrown. Keep you guys posted!
 
This post has been deleted
#42 ·
My 2021 with 50K miles on it just started with this today.. I also noticed when i got out of the car the cooling fans were locked on high and werent turning off (been inside a few mins have to check if they are still on), but Dammit man this is such an annoyance. I lease this car, and just ANOTHER thing in the long line of issues i have had with it, which really make me wonder do i switch brands or re up for a 2024.
 
#45 ·
Just an update. I took the Acadia in this morning.. The last 2 days, the Steering Assist message, coinciding with my Temp Gauge flatlining to Cold, it all as everyone points out looks like thermostat or temp sending unit.. It threw the check engine light on for one night.. then the next morning, it all fixed itself, temps normal, no error, no check engine light... then it happened again whilst driving.. Steering assist message and temp gauge clanked to C. So i took it into GMC this morning, $159 diagnostic fee and we will see what they come back with soon.
 
#47 ·
Let us know if the problem comes back before your lease expires or you buy something else.
Some have replaced the thermostat and the issue returns.

There seems to be a question of whether the problem is the actual thermostat, the Engine Coolant Temperature sensor right next to it. . . . or even the short wiring harness and connector that is attached to the ECT sensor.
 
#48 ·
This happened to me again for the 3rd time. Its been on and off. 2019 3.6 SLT 68,000mi out of warranty.

The part is on backorder with all my local dealers (12678779) about a week out or two. Its starting to get hot! ill try the batt terminal cleaning and ill use my scan tool and hopefully it will fix it long enough until the Genuine GM part is back in stock.

I even checked for aftermarket ones, all on backorder , Dorman 902-2115, MotoRad 860-221, AC Delco 15-11122.

I know ill need intake manifold gaskets ( 12648665) and a coolant temp sensor ( 12650595) anything else while I'm in there?
 
#49 ·
This happened to me again for the 3rd time. Its been on and off. 2019 3.6 SLT 68,000mi out of warranty.

The part is on backorder with all my local dealers (12678779) about a week out or two. Its starting to get hot! ill try the batt terminal cleaning and ill use my scan tool and hopefully it will fix it long enough until the Genuine GM part is back in stock.

I even checked for aftermarket ones, all on backorder , Dorman 902-2115, MotoRad 860-221, AC Delco 15-11122.

I know ill need intake manifold gaskets ( 12648665) and a coolant temp sensor ( 12650595) anything else while I'm in there?
You will need two o-rings for an associated coolant tube that needs to be removed as I recall.
Here's the list of parts:
Manifold Gaskets x6 Part# 12648665
O-rings for the 2 return lines x2 Part#12648547
Thermostat assembly and water pipe Part# 12678779
Engine Temperature Sensor (might as well replace this $12 part at the same time) *This one you can get anywhere Part# TX281
 
#54 ·
I have a 2018 Acadia Denali & it is showing the Steering Assist Error Message which I believe is something with the Thermostat. Can someone please quickly explain the cause of this problem & what the Solution is? I want to be able to present it to the dealer if they try and tell me the problem I'm having is something else.


Thank you,

Dan
The thermostat is defective. I had mine replaced and the issue is fixed.$765.00