: cluster message: ENGINE HOT - AC OFF



bjherron123
02-03-13, 12:08 AM
got a wierd message today. I was driving in the snow, 8 degree michigan weather. After 10 minutes of driving, and 4 minutes from home, the cluster said ENGINE HOT - AC off. It then disabled my AC. I tried to turn it on just to see, and it wouldn't come on. At the same time, my temp gauge needle stopped working and went to the cold side.

I used the dash to determine that engine oil temp was 158 and not rising. Trans temp was 98, so I kept driving (did I mention it was snowing). Got home, and did notice the cooling fans running on full as I pulled in the garage.

anyone have this happen? still covered under the CPO, but this may be hard for them to reproduce.

Brian

carter's_sts
02-03-13, 02:27 AM
From reading on here, that message can mean overheating (not in your case) or it means the coolant temperature did not get up to a certain value in a certain amount of time (stupid).

Usually its the thermostat, but with your temp gage going to the bottom, it might be the coolant temp sending unit.

PGA2B
02-03-13, 10:52 AM
Yes, a lot of us have had this happen. It's the Thermostat.

Fierofiend
02-03-13, 10:55 AM
Coolant temp gauge always goes to zero when this happens. Do a search, this has happened to almost all of us,lol. Its as he said, not getting up to temp,usually a thermostat. The computer really needs a software update to fix this issue, Cadillac should have realized this by now.

Berger 93
02-04-13, 11:11 AM
Still contending with this . . weather went south and have not had a chance to get the car out . . . and now the battery died . . buh . .

carter's_sts
02-04-13, 11:34 AM
Battery tender. I plug mine in usually for the whole week, since its mostly a weekend car.

YoungBlood_STSV
02-04-13, 04:21 PM
In 8 degree weather I would let it slide this time. If it does it multiple times as the weather warms up you need a new t-stat. Simple Fix.

brbevil
02-06-13, 03:12 PM
Just happened to me last month. Easy fix. Be sure to take your existing thermostat to the parts store. Advance auto parts had two listed. Unfortunately the one I bought was too big. Second time worked perfectly. Took me about 4 hours. I am a complete novice and spent lots of time looking around checking other things out. Good luck. Oh FYI. Thermostat was 15$ if I remember correctly but had to get new gasket from dealer. It was 8 dollars.

terrydactul
02-06-13, 10:11 PM
I had the same thing a few weeks, took it to the dealer under warranty..they replaced the Thermostat and problem solved.

tino160
02-11-13, 11:03 PM
Mine started this today. Showed the messaage and temp gauge stays on cold the whole time as soon as i start it up. I am guessing it's the temp sensor and not the thermostat since it does it as soon as it starts. Am I rite?

PGA2B
02-11-13, 11:06 PM
No. Thermostat.

tino160
02-11-13, 11:15 PM
Thanks, I will pick one up.

rwwrrr
02-23-13, 05:46 PM
Mine has done this for a week now. Last time it just went away. Guess I am off to auto parts store.

JeffB13
03-19-13, 04:52 PM
Yup, Thermostat. Happened to me last summer in the middle of a 2 hr trip.

theotherguyssn
04-05-13, 11:20 AM
there is also a update for the engine control module for it setting a p0128 intermittantly. coolant not getting to operating temp, mine did it right after i bought it put the install in as well as a thermostat just to be safe

PGA2B
04-05-13, 12:13 PM
Now that I am in AZ I am not worried about the code but since I was in Missouri when I did the T-Stat and have HP Tuners, I just shut off that code just in case. Most of the time when the T-Stat goes bad it does not even set a code. I think that causes a lot of the confusion when this issue pops up.

terrydactul
04-06-13, 09:32 PM
I just had my thermostat replaced for this same issue

eatonup1
04-11-13, 03:22 AM
I actually had screws back out from the fan shroud into the blade path that prevented them from turning...BUT my buddy at the dealer was able to rectify it, get me a new thermostat, and new A/C clutch...

indabackofdalac
04-16-13, 01:54 AM
Chiming in to say thermostat was at fault for this same message on mine while the previous owner had it... dealership diag'ed it as such.

bjherron123
04-30-13, 04:39 PM
just an update. Took this to the dealer to get this issue resolved under my CPO warranty. They said they couldn't find any problems and refused to change the thermostat after holding on to my car for two days.

I guess I will just do it myself. I am looking forward to when this warranty expires so I can pick where the car goes for maintenance and get real service.

Brian

Berger 93
05-01-13, 10:46 AM
just an update. Took this to the dealer to get this issue resolved under my CPO warranty. They said they couldn't find any problems and refused to change the thermostat after holding on to my car for two days.

I guess I will just do it myself. I am looking forward to when this warranty expires so I can pick where the car goes for maintenance and get real service.

Brian

Sadly the same experience I had . . . whether it is the dealers or GM . . . unless they have a specific "code" stored in the computer AND they can duplicate it they will tell you nothings wrong with the car . . completely infuriating . .

Service blows . . . and most likely applies to all cars . .

theotherguyssn
05-01-13, 12:04 PM
yea man you need to put a thermostat in the car with a new gasket, prolly set a p0128 dtc when it gets that code it disables temp gauge in vehicle, need to check your coolant resvoir make sure its full of course make sure no leaks but need to stick a thermostat in it, i had it happen to mine last month right after i bought the car luckily im a gm tech so was no prob was little aggrevating to get to the two nuts but if you pull the center section of air duct b/t y-pipe and air box off you can get to it. also is a pcm calibration update through gm i found that is suspose to fix intermittant a/c hott message as well but would have to take to gm dealer see if your pcm needs the update. thermostat with gasket was under 30 bucks through dealer though