An appointment Monday is the right approach. The dealer should be able to see the codes that were set when the check engine light came on. That will be evidence of what is going wrong.

 

Wet, slipping serpentine belt on the p/s pump ???

 

It’s Electric power steering. No pump

 

Well according to the dealer mechanic it is related to a faulty thermostat (internal?) and the part needs to be replaced.
Although the connection confuses me, I now remember that when the check engine light was active the engine was idling extremely fast. Thankfully this still falls under warranty. Appreciate all the input and will especially ask about the Electric powersteering suggestion.

 

Well according to the dealer mechanic it is related to a faulty thermostat (internal?) and the part needs to be replaced.
Although the connection confuses me, I now remember that when the check engine light was active the engine was idling extremely fast. Thankfully this still falls under warranty. Appreciate all the input and will especially ask about the Electric powersteering suggestion.

Did you get this repaired yet? I have had this same thing happen about 5 times now. The first time the dealer told me my battery failed testing and that ended up costing me $197 to install a new one since batteries are not covered. Guess what, it happened again this week. So it is going back to them next week. When I get this message I have no AC and the Start/Stop feature stops workinig, not that I really care about the Start/Stop anyway, but still.

 

Good evening. On my first visit to the dealer here is what was reported. P073 Shift to reverse, P07E4 shift to park. Performed Bulletin No 18 NA-083. Check and updated TRCM, module and chasis control module was current. Performed back up park lock adjuster and calculated leaing proceure. Calculated Trans Range control reset.

Last week following the check engine light coming on and staying on and the Steering Assist Reduced message, it was diagnosed Fault P0128, found the thermostat opening too soon and setting fault. Thermostat Binding internally.
Diagnosed R&R intake and fuel injectors, replaced the coolant thermostat housing assembly and replenished coolant and bleed system.
I hope this helps you and I'm really hoping this will solve my message issues i've had for the past year!
I also took photos of the messages and dated them so when I went in they listed the problems and dates. I wanted a runnign list of problems and dates.
good luck!

 

Good evening. On my first visit to the dealer here is what was reported. P073 Shift to reverse, P07E4 shift to park. Performed Bulletin No 18 NA-083. Check and updated TRCM, module and chasis control module was current. Performed back up park lock adjuster and calculated leaing proceure. Calculated Trans Range control reset.

Last week following the check engine light coming on and staying on and the Steering Assist Reduced message, it was diagnosed Fault P0128, found the thermostat opening too soon and setting fault. Thermostat Binding internally.
Diagnosed R&R intake and fuel injectors, replaced the coolant thermostat housing assembly and replenished coolant and bleed system.
I hope this helps you and I'm really hoping this will solve my message issues i've had for the past year!
I also took photos of the messages and dated them so when I went in they listed the problems and dates. I wanted a runnign list of problems and dates.
good luck!

I also just had this happen on my 2017 xt5 platinum brought it for service yesterday my engine light is on but not all the time and I keep getting the steering assist warning
The Cadillac dealership service said the engine light is on due the message but they see nothing wrong they think it’s something to do with the coolent? It was low so they added dye to it I need to go back in 150 miles to get it rechecked I’m really not impressed with this vehicle my 3rd Cadillac this car also had a bad headlight condensation the reason I traded in my srx !! They did change it out for free so I’ll let you know if they find out what’s wrong I’m going on 63000 I think I might trade🙁considering they want to give me only 24500 for a platinum I will not be buying another Cadillac

 

Thank you @Sypagen. I have also been taking pics when these messages appear. It's amazing that it is so hard for them to figure out what is going on and it seems this problem is probably reported a lot by now. I hope they fixed your issue but I will be letting them take a look at the info you posted to see if they can come up with the same error codes.

 

I highly doubt a thermostat problem has anything to do with a steering assist message. Two completely different systems.

 

I wouldn't be surprised. On my previous vehicle, a fuel pump error code disabled cruise control. Periodically the idiot light would go out, and cruise control would come back, only to go away a few hundred miles later when the light came back on. Why? No idea.

 

Ok, got my vehicle back tonight and I am going to post exactly what is on my invoice for future reference on these forums. Hopefully what they did fixes this issue.

"Verified-scan, found U0140-Invalid Data From ECM & P0128 insufficient temp in ECM. Check coolant level-OK Check ECT reading in ECM data with GDS, Never goes above 185 deg, Check temp readings at T/STAT with inferred temp gun, TSTAT stuck open, Remove intake manifold, fuel rails & replace thermostat/water outlet pipe, Re-assemble, fill & bleed coolinig system, clear codes & test drive - OK...Replace water outlet/thermostat 4032830"

All of the above was under warranty with no deductible. Fingers crossed!

 

Ok, got my vehicle back tonight and I am going to post exactly what is on my invoice for future reference on these forums. Hopefully what they did fixes this issue.

"Verified-scan, found U0140-Invalid Data From ECM & P0128 insufficient temp in ECM. Check coolant level-OK Check ECT reading in ECM data with GDS, Never goes above 185 deg, Check temp readings at T/STAT with inferred temp gun, TSTAT stuck open, Remove intake manifold, fuel rails & replace thermostat/water outlet pipe, Re-assemble, fill & bleed coolinig system, clear codes & test drive - OK...Replace water outlet/thermostat 4032830"

All of the above was under warranty with no deductible. Fingers crossed!

Hi, I got the ‘Action Required: Steering Assist is reduced...’ warning on my 2017 Xt5. I just bought car used with 12k miles on it, and this happened 3 weeks after buying it for 2 days and then it went off. I called dealer and they passed me to the mechanic department and he said he had never heard of this. I want to take to dealer while I have a warranty to have them fix this, but now light is off.
I am seeing this is a problem for this year and model. Hoping what you had done fixed your issue and had helped others as well. I will share with them your thread. Thank you!

 

With the thermostat stuck open, the engine not only was not reaching operating temperature at only 185 degrees, but it was always taking an extraordinarily long time to get to even that temperature. All of the technology designed and programmed into the engines of these vehicles is very dependent on reaching a normal operating temperature in a very short amount of time.

 

 

After dealing with the constant messages popping up after being at a stop and the auto stop engaged, I followed the advice of another post. I had previously had some issues with the battery voltage and even a dead battery after the car had sat for about 10 days. I took it to the dealer and insisted on a new battery (it was reaching the 4-5 year mark anyway) installed. The dealer didn't agree with me, but I had a new battery installed. It has been 3 weeks and I have not had any issues with messages appearing wen stopped or sitting at a stop light and reengaging the engine. I'm hoping that this will solve the problem of constant messages.

 

Our shade tree mechanic wisdom and experience has been outpaced by the new electronic controls in our vehicles.

 

I have periodically had this message pop up on my message center dashboard. I think that it is related to weather/rain/carwash ( I think I had seen this on the forum last year).
I also occasionally have the check engine light come on also. Example: last Tuesday the Steering Assist message came on, then after several stops and starts the check engine light came on and both stayed until Friday. Then they both disappeared(turned off). Saturday evening (yes, it rained) the Steering Assist Reduced message returned. I have an appointment scheduled for Monday, but would like to go to it armed with more knowledge than I currently have. All information would be appreciated. Last January I had several messages constantly popping up on the dashboard and the dealer did a software update which seemed to help.

I recently purchased a 2017 XT5 that was a previously owned (one owner) "Certified" vehicle with the 3.6 L engine. So I am responding to this because I too recently saw this "Steering Assist Reduced" message when I also experienced a reduced throttle response suddenly. The Check Engine light came on as well along with several other waring indications on my dash display. Only been driving the car for 4 weeks.
Set up an appointment for service for the very next morning (Monday). Although the dealership was not too far away, I still hoped that I wouldn't have an issue driving it in since the transmission seemed to also be malfunctioning. But the car did drive well enough and I got it checked in. They had it a little more than 2 days. I just returned home with the car and it does seem all is right again. The work was under warranty. The Check Engine light was diagnosed as a cylinder misfire on #5. Plug and coil inspected good. But a tech info bulletin search on "misfires on #5" indicated that the AFM (Automatic Fuel Management) Solenoid / valve was involved and it was replaced on cylinder #5. A 35 mile test drive turned up no new power train codes and no misfires. Additionally, this "certified" (?) used vehicle was found to need some new software updates to engine and transmission modules.
The good news .... the drive home from the dealership service facility was completely uneventful. The "Steering Assist Reduced" warning never really was noticed as an actual issue. Did not notice any difference in the steering. The transmission and throttle response however WAS very much a problem.
Please reply if this post is helpful and especially if you have any technical insight or detail / experience with the subject of this post. I have found that the AFM Solenoid / valve is part of the cylinder deactivation at cruse speed to increase fuel economy.

 

I recently purchased a 2017 XT5 that was a previously owned (one owner) "Certified" vehicle with the 3.6 L engine. So I am responding to this because I too recently saw this "Steering Assist Reduced" message when I also experienced a reduced throttle response suddenly. The Check Engine light came on as well along with several other waring indications on my dash display. Only been driving the car for 4 weeks.
Set up an appointment for service for the very next morning (Monday). Although the dealership was not too far away, I still hoped that I wouldn't have an issue driving it in since the transmission seemed to also be malfunctioning. But the car did drive well enough and I got it checked in. They had it a little more than 2 days. I just returned home with the car and it does seem all is right again. The work was under warranty. The Check Engine light was diagnosed as a cylinder misfire on #5. Plug and coil inspected good. But a tech info bulletin search on "misfires on #5" indicated that the AFM (Automatic Fuel Management) Solenoid / valve was involved and it was replaced on cylinder #5. A 35 mile test drive turned up no new power train codes and no misfires. Additionally, this "certified" (?) used vehicle was found to need some new software updates to engine and transmission modules.
The good news .... the drive home from the dealership service facility was completely uneventful. The "Steering Assist Reduced" warning never really was noticed as an actual issue. Did not notice any difference in the steering. The transmission and throttle response however WAS very much a problem.
Please reply if this post is helpful and especially if you have any technical insight or detail / experience with the subject of this post. I have found that the AFM Solenoid / valve is part of the cylinder deactivation at cruse speed to increase fuel economy.

I had this same cylinder misfire issue on my 2017 XT5 a few months ago. When the warning lights lit up the console the vehicle felt like it was suddenly stuck in 3rd gear. It was very troubling as I was doing 65mph on the expressway and was both 20+ miles from my house and my intended destination with my children in tow. I got off the expressway to take local roads since the car couldn't handle the speeds but then had problems getting the car to go on any incline after coming to a stop. At one point some strangers standing on the corner gave it a push to get me moving again. After the way it drove I was shocked that the problem was an under $100 fix, though it was covered by warranty.

 

Very similar to what I experienced. My car was still under warranty as well, so the only cost to me was 3 days without any transportation other than Lyft service. So in reading the details of what was done to diagnose the problem, it was due to a sticking solenoid that is part of the Automated Fuel Management (AFM). This is a system that allows our 6 cylinder engines to cruse using only 4 cylinders. This is one way of conserving fuel. That may be the case if you are driving on the highways a lot or on long trips. This malfunctioning solenoid cause the # 5 cylinder to misfire which was the reason for the Check Engine Light. The misfire prompted an inspection of the spark plug and coil for that cylinder, which were confirmed to be undamaged. But since I felt that the transmission was possibly also malfunctioning, there was a diagnostic run on that which found no issues ..... but did show that there were software upgrades available for both the transmission and engine modules. After a 35 mile test drive and another check with the diagnostic instruments to insure there were no other issues, I was given a call to drive it home. My observation from this experience is that possibly these new vehicles with all the bells and whistles / conveniences, will need far more awareness of service schedules and "hiccups" in the day to day operation of the car.

 

My car was still under warranty as well, so the only cost to me was 3 days without any transportation other than Lyft service.

Why didn’t the dealership provide you with a loaner car?

 

Yeah, that was what my wife was wondering about. I did ask and it seems that at the dealership in Carlsbad requires notice in advance to reserve one of the "Courtesy" vehicles. I can see that. Seems they give priority to people that are bringing their cars in for regularly scheduled service.

 

Cadillac reimburses the dealer for the cost of a loaner as part of warranty repair.

 

Thanks for that info. I'll be sure to remember that when next I need to leave my car in the service department. I guess the actual issue was that they only had a specific number of vehicles for the "Courtesy" car loaners.

 

If they do not have loaners on hand, they can rent a vehicle for you. Cadillac pays.

 

Appreciate your response. In my case at the dealer I chose to use, did call and pay for the Lyft service to get me home and back to the dealer to pick up my vehicle. But I will be reserving a courtesy vehicle whenever I need to have my car serviced if it is an overnight deal, or when I need work done that I can schedule the work in advance.

 

Same issue here except it is recurring now.

My XT5 showing the Message “Steering Assist is Reduced Drive with Care”, the thermostat sticks to C (cold) and the AC won’t work.

3 weeks ago the service department had the vehicle for a full week as it would not produce any codes. Eventually they replaced the thermostat sensor and all seemed well for a couple weeks.

Today the issue is back. After restarting the car 6 times however the check engine light finally came on. Which I’m hoping is a good thing to detect the root cause. The diagnostic email stated “An issue with the Engine and Transmission System in your 2017 Cadillac XT5 has been detected. Please service your vehicle within 7 days”.

6 months ago my wife parked the car to go into the store, on her return when attempting to start the car the brake pedal wouldn’t depress.

Had the car for a year now - pretty annoying.

 

The diagnostic email stated “An issue with the Engine and Transmission System in your 2017 Cadillac XT5 has been detected. Please service your vehicle within 7 days”.

If you received an email, there must be a code stored.

 

So, is anyone on this thread that owns or has owned a 2017 XT5, thinking this is a chronic issue with this year of this vehicle? I am certainly wondering if this is the possibility. I have only seen one occurrence of a similar issue with my one owner "certified" used 2017 XT5 that I just purchased at the end of Jan. So far, since I got the car back from dealer service where it was found with a "sticking AFM solenoid" that caused a misfire in cylinder #5 with the "Check engine" light notification, all seems well. Service tech checked the plug and coil for that cylinder and found no damage. There were some software upgrades for the transmission and motor modules installed. Sure is on my mind whenever I am driving it though. Driving it rather carefully and very aware of any unusual shifts or buggy things in operation. The complexity of the vehicle electronics is constantly on my radar since I am a retired electronic technician. These systems should be robust enough for the vehicle but during my career I have frequently seen the the first generation of software to be prone to issues, as one would expect If I am correct, 2017 is the first production year of this XT5 model. Anyone know if this is correct?

 

If I am correct, 2017 is the first production year of this XT5 model. Anyone know if this is correct?

That is correct.

 

For my repair it was covered under the power train warranty.

mans fortunately after a couple rounds I haven’t had this problem again (knock on wood).

 

@Shafer123457 can you tell me how many miles were on your car, and the model year?

 

I had a similar issue and it was related to a dying battery.

 

I recently purchased a 2017 XT5 that was a previously owned (one owner) "Certified" vehicle with the 3.6 L engine. So I am responding to this because I too recently saw this "Steering Assist Reduced" message when I also experienced a reduced throttle response suddenly. The Check Engine light came on as well along with several other waring indications on my dash display. Only been driving the car for 4 weeks.
Set up an appointment for service for the very next morning (Monday). Although the dealership was not too far away, I still hoped that I wouldn't have an issue driving it in since the transmission seemed to also be malfunctioning. But the car did drive well enough and I got it checked in. They had it a little more than 2 days. I just returned home with the car and it does seem all is right again. The work was under warranty. The Check Engine light was diagnosed as a cylinder misfire on #5. Plug and coil inspected good. But a tech info bulletin search on "misfires on #5" indicated that the AFM (Automatic Fuel Management) Solenoid / valve was involved and it was replaced on cylinder #5. A 35 mile test drive turned up no new power train codes and no misfires. Additionally, this "certified" (?) used vehicle was found to need some new software updates to engine and transmission modules.
The good news .... the drive home from the dealership service facility was completely uneventful. The "Steering Assist Reduced" warning never really was noticed as an actual issue. Did not notice any difference in the steering. The transmission and throttle response however WAS very much a problem.
Please reply if this post is helpful and especially if you have any technical insight or detail / experience with the subject of this post. I have found that the AFM Solenoid / valve is part of the cylinder deactivation at cruse speed to increase fuel economy.

My replacement was also covered under the warranty. Not sure, however, that did not solve the problem until I replaced the battery. My battery was about 3-4 years old and even though I was told it was still good, insisted on replacing it. I have not had the issue since.

I’m not sure if I’m replying in the right place, but my 2017 xt5 just started having this same issue. I’ve had it a year with no issues. Unfortunately, mine only had a 30 day warranty from the dealer because it was a used vehicle. Thank you all for this useful information. I think I’m going to see what the code says and then replace the battery before I spend a ton of money. I did see one post that said it was covered under the powertrain warranty. Maybe that would work with mine. Always hopeful.

 

I’m wondering if it’s still OK to drive?

 

It should be safe to drive but with increased steering effort. Any good, local Mom & Pop auto shops in your NE area? NOT some Oil Doodle or muffler shop chain.

The dying battery references - does your engine start quickly, lights and toys work OK? Sort of a stretch, but a 2017 battery may be on its last legs - but how that affects the (electric) steering is also a stretch - once the engine is running.

Check, or have checked, the red connector distribution box on the positive battery terminal.

 

Will do! Thank you!!

 

My g/f's 2017 just had the same problem today. Steering Assist Reduced message, fan on continuously and the temp gauge on cold and not moving up at all. Brought it to my local dealer and they took it in right away and changed the coolant temperature sensor and replaced the thermostat and added coolant. Fine now and great service.

 

My g/f's 2017 just had the same problem today. Steering Assist Reduced message, fan on continuously and the temp gauge on cold and not moving up at all. Brought it to my local dealer and they took it in right away and changed the coolant temperature sensor and replaced the thermostat and added coolant. Fine now and great service.

Thermostat is becoming a pretty common repair on these XT5’s.

 

Does anyone know if the powertrain limited warranty covers this issue. I am having the same problem but no check engine light comes on (at least at this time). Same steering assist message, temp gauge stays at C, fan seems to be running like crazy but not cooling the car. Thanks

 

Yes, I believe it would be covered.