: 2008 DTS overheats



maudeaub
08-24-13, 03:39 PM
I have a Cadillac DTS 2008 and it is overheating, I can drive for about
40 minutes then when I stop at a red light the temperature gauge goes
up, if I remain idle in traffic for a long period of time, the car will
overheat and show a display of A/C overheating engine shutting off
it does not say anything about coolant, the thermostat was changed
but on the right side of the car by the compressor I hear a little
rubbing sound early in the morning when I start the car up, I took
it too autozone for a reading and there was no code, the technician
started the ac and saw that the cooling fans were not running and said
that it could be the compressor for it activates the fans, has anyone
had any experience with this? Or am I on the right track?

Submariner409
08-24-13, 03:43 PM
Let's put this in its own thread instead of hijacking one that has nothing to do with "overheating".

If the fans (plural - your car has 2 fans and they run together) are not running in SLOW any time you set an A/C function then something is wrong with either the fans, the wiring, the fan fuses or relays, or the commands necessary to turn on the fans.......... and any of that WILL cause an overheat situation.

Start with the maxi-fuses and fan circuit fuses in the underhood fuse box - check them for continuity then move to the fan relays - there are 3, two 4-pin relays, one 5-pin. They are TIGHT in their sockets, but oxidation of the blades and sockets can occur. Remove and insert each relay 3 times.

Any large auto parts chain store can use your diagnostic system to get any stored trouble codes - most of the fan operations are monitored, so when you get the codes, use the sticky above this - "How to pull codes" - to get to a link of all trouble code definitions. You cannot get the codes yourself - that went away in about 2005, but the storage system is still there: You want the code definitions.

Go down to Engines: Northstar Performance and read the 3 sticky posts on fan operation, gauge operation, and the cooling system.

69ssc5
08-24-13, 04:00 PM
deleted

Submariner409
08-24-13, 04:38 PM
It's all explained in the cooling stickys in Northstar Performance. Her car has 2 fans which run together - either SLOW or FAST, depending on A/C configuration, engine coolant temperature, or even transmission fluid temperature.

Fan circuit diagram in my albums.

Cadillac Cust Svc
08-24-13, 07:45 PM
I have a Cadillac DTS 2008 and it is overheating, I can drive for about
40 minutes then when I stop at a red light the temperature gauge goes
up, if I remain idle in traffic for a long period of time, the car will
overheat and show a display of A/C overheating engine shutting off
it does not say anything about coolant, the thermostat was changed
but on the right side of the car by the compressor I hear a little
rubbing sound early in the morning when I start the car up, I took
it too autozone for a reading and there was no code, the technician
started the ac and saw that the cooling fans were not running and said
that it could be the compressor for it activates the fans, has anyone
had any experience with this? Or am I on the right track?
Hello maudeaub,

I apologize that your DTS is overheating because the fans are not running. I do see that Submariner409 has given you some great input. If you will be taking your vehicle to the dealership in regards to this concern, I would like to assist you. Please private message me your name, contact info, VIN, mileage, and dealership you will be working with if you are planning on taking your vehicle to one. You can also reach out to me at socialmedia@gm.com if you are unable to private message me. Please include “ATTN GREG” in the subject line so it gets delivered straight to me when you send your email. Thank you very much for your time.

Gregory W.
Cadillac Customer Care