2001 s80 Coolant Low, Stop Safely / Stop Engine Message, faulty sensors????

Question:

OK, so my 2001 s80, non-turbo, "the sled" as it is named has a small
issue. In the morning, every morning, my volvo will display "Coolant
Low, Stop Safely" as well as "Coolant Low, Stop Engine" and it is
switches back and forth between the two with no consistancy, as in it
will switch back and forth like it can't make up it's mind as to if it
wants me to stop safely or stop engine. Also, I can time it, I drive
down my street and as I pass by a certain stop sign, the message will
go away and it will not show up again until the next day when I start
my car. Also, I have repeatedly checked for fluid leaks and a lack of
coolant, neither of which it has. My car never goes over the dead
center of the middle of the temperature guage, no signs of any kind of
overheating. When I got the car a year or so ago, this reared its
head 2 or 3 times, but it went away and I didn't worry about it.
Also, my car will turn the fan blowers on in the cabin on by itself,
no key in the ignition, when it gets hot really outside (80-100+
degrees, Socal weather) again sporadically, unrelated I think, but the
only other apparent issue with the car. My first inclination is a
faulty sensor of some variety, and I know I can swap sensors. Where
should I start? Thanks!

 

I have a 2001 S80 T6. I haven't seen any coolant messages so can't help
there. The fan blower operation is a normal event and not temperature
related. It comes on an hour after shutdown and runs for a period of time
to dry any condensation in the A/C system.

Allen

 

wow.. thats kind of crazy I have never heard of that before, I was
kind of worried that it was going to drain the battery, never has
happened, but the car definitely will turn over slower after a period
of the blowers being on.. has it ever drained your battery?

 

I had to replace the original battery about 4 months ago. That is the only
time the car would not start.

Allen

 

Well, you have to love volvo, they have to get the award for over
engineering every last detail, the same reason I love my care is the
same reason it scares me... they do not follow the K.I.S.S. thoery of
auto design... I mean come on, drying out the condesation in the AC
unit? Isn't that a little over zealous?

 

Have you checked the coolant level when cold to see if it is above the
minimum marker. On my 2000 S80 if the level is slightly below minimum
the light will flash on and off as the coolant sloshes around, but
once warm it has expanded enough to no longer trip the sensor.

As Allen mentioned the car computer is set to run the blower about 1
hour after the AC was run. That removes any remaining moisture from
the evaporator and helps to control mold buildup. It works.

 

I think Roadie is on the right track. Dunno about the S80, but most cars
with a "low coolant" indicator are telling you the level in the reservoir is
low. Those sensors fail fairly often, but be sure the level is right.

Mike

 

Well, I did notice that the coolant is down near the minimum line when
I have verified that the coolant was not leaking or below low, but I
wasn't thinking that being so close to the minimum would be a
problem. I want to add some coolant to this bad boy, but it says
"Volvo Coolant only" is this total BS or should I go buy it at the
dealer? Other lead in question, since the blowers come on like that
sometimes (rarely 1-2 times) the car does a weak start, like it takes
longer to turn over, should I buy the Volvo battery or will any due?
I heard some car manufactures build their cars to only work properly
with some brands of batteries?

 

Hey mike, thanks for the follow up, I'm going to try to add coolant,
it is hovering at the minimum line...

 

ps...THANKS IN ADVANCE YOU RULE!

 

You'd think so, but... in the early '90s, following changeover from R12 to
R134a and the redesign of the AC system that involved, several automakers
had a rash of evaporator failures. The early 850s were hit especially hard.
Mysterious pinholes would form in the evaporators after only a year or two
and a very expensive repair followed. The problem was traced to corrosive
mud that formed when dust and pollen collected in the condensation on the
surface of the evaporator. The first fix, one that was widely adopted, was
the addition of cabin air filters. It helped a lot but must not have been
quite enough. Volvo and Honda (also badly affected by evaporator failures)
have now programmed the HVAC fan to dry out the evaporator after use. Other
makers may be doing that, too.

Mike

 

I confess I'm bewildered by the various types of antifreeze in use now. The
safe thing to do is to add a pint or so of distilled water. It's compatible
with any coolant! Eventually somebody here will have the full answer, but
the water is a good start.

Mike

 

If you have the car serviced at the dealer just drop by and ask them
to top it off. If you are a regular customer chances are they will do
it gratis. Otherwise, I would go with the Volvo brand. Next issue to
consider is what caused it to go low in the first place. The cooling
system should be pretty close to a closed system, so you may have a
very slow leak somewhere. To find the leak will take someone with the
eyes and experience to locate it. My suggestion is to have a good
volvo mechanic look it over.

When it came time to replace the battery on my 2000 S80 I checked out
prices of good quality comparable brands and found they were close.
The battery for this car has a vent which must be connected to allow
explosive hydrogen gas to vent to the outside. I went with the Volvo
battery mostly because it was set up with the proper tubing and
required no adaptors as the after market batteries do.

No that isn't true. But some batteries do have special vents for
proper expelling of hydrogen gas and the terminals are placed to allow
the battery to fit into a sometimes small location. Consequently not
every brand will work. But most will.

If you decide to replace the battery yourself realize it is in the
trunk under a trapdoor and the process is a bit fiddly, but doable by
the home mechanic. Be sure to read the instructions throughly in the
battery compartment. It is very important that you follow the
sequence of detatching and reattaching terminals exactly or you could
fry some electronics. Also be sure to clean the battery clamps
throughly to remove any acidic oxide. And finally be sure to clamp
down the battery properly.

 

Thanks for the response,

I was waiting to see what was going to happen after a few mornings of
cold starts. I have added some coolant to the car and since the error
message of Coolant Low, Stop Engine or Coolant Low, Stop Safely has
stopped coming up. Nonetheless, I am going to have the car inspected
to verify that there are no small leaks that might cause future issues
down the road. Thanks so much for you expertise and opinions!

 

I have a Volvo S80 T6 Turbo, and I had the same issue. After replacing the thermostat (at the bottom of the coolant reservoir) all I had to do was reset the service menu and it was fixed. hope that helps.