jimxms2

Guys, I just bought my LS460 a few weeks ago and I'm having problems finding out how to use the heater controls in the car to warm me up on these cold British mornings.

When I leave all of the heater/AC options to 'Auto' and increase the temperature controls, it just blows out cold air to the footwell and nowhere else. Changing the circulation options doesn't seem to help either.

The only thing that seems to work is switching off the A/C option, but this then means that the windscreen mists up within about 30 seconds.

Should it be this difficult to get hot air? In all previous cars I've just left everything to Auto and dialed in the temperature I want.

As a sidenote, I thought the car had infrared temp sensors? Can't it see my feet suffer from frostbite when it pumps cold A/C into the footwell when it's -5c outside!

Lextrician

signs of a dirty cabin filter will cause the moist windows... check your coolant level as well.

jmcraney

I think you can have either temperature scale, Celsius or Fahrenheit, so since you are accustomed to the "C" scale be sure that you know what temperature you are requesting. The fact that it is drying the air, no condensate on the windows, then the cooling part, which works in both the cooling and heating modes, is working. If you are using the "F" scale mode you would want something like 76-80, and if you are using the "C" scale then you would want something like 24-27.

jimxms2

Will check the coolant level in the morning, but it seems to be getting up to temp at an acceptable rate and the temp gauge sits right in the middle.

@jmcraney - The UK LS460 displays temps in C, so I've been setting it around 23c (outside temp 6c today). It goes up to about 30C before hitting the max.


Strangely, before I purchased this LS460 I looked at another one where the dealer (private) was telling me that he couldn't work out how to make it hot either. So either this is a common issue, or neither of us know how to work the heater lol :/

jmcraney

Look at the coolant temperature gauge, on the left side of the speedometer, and make sure it is getting up to mid range after you have driven your car for a few minutes.

danyeru

Having similar problem with my 03 GS 300... it does heat up but is now taking 15 minutes instead of 5 and only sends heat if its set to max temp and I am on the throttle.

jmcraney

Those are classic symptoms of a bad thermostat, the one that controls the coolant flow to the engine.

Look at the coolant temperature gauge, on the left side of the speedometer, and make sure it is getting up to mid range after you have driven your car for a few minutes.

The heater should act normally when the coolant temperature gauge reaches normal (mid range).

jimxms2

Mine seems fine in that regard. Up to temp by the time I've done a couple of mins driving.

Weirdly, today I took the family shopping and it was pumping out warm air quite quickly without me changing any settings :/

JFNash

I think I recall something similar happening to me, but I couldn't remember if I got it to work or not.

Try to set it manually. Don't use the auto option. I think it'll work.

Just set the air blow level and raise the temperature to the max and see if it works.

jimxms2

Slight update:

I opened up the coolant reservoir today and it hissed and gurgled lots. Interestingly the coolant level went down from being between MAX and MIN to being below MIN. So I'm going to get some premix pink from the dealership on Monday and top it up.

I did get a puff of heat this evening, but it was short lived :/

jmcraney

My car is equipped with the touchscreen navigation system. On the left side of the screen, in the hard key cluster, is a button that says "Climate" I believe. When I press that button a climate control screen appears on the touchscreen display. I have that set to automatic. And, in the dash, below the touch screen there is another AC control panel and I have that set to automatic too and that is where I adjust the temperature. The fan control is automatic and air flow is primarily through the floor ducts, with some to the base of the windshield and the side windows for defrosting when the demand is for heat and the air flow is primarily through the dash vents when the demand is for cooling. I have not investigated how the two different controls interact.

As for the coolant reservoir, you would only want to remove that cap when the engine is cold and check the level when the engine is cold and add coolant when the engine is cold. And the cap on the reservoir should be tightened until it "clicks" as that insures that the system will pressurize and the boiling point of the coolant is raised when the system is under pressure.

jimxms2

UPDATE: My car has heat!....but only when I rev the engine past 2k or generally thrash the car around a bit.

What gives??

jmcraney

I think you have lost most of your coolant possibly due to a leak. Fill the reservoir and tighten the cap when it is cold then check it again, after you have driven it, when it is cold. If you are in subfreezing conditions then you need to check your coolant with a hydrometer as your problem may be due to ice formation.

jimxms2

Thanks man I'll give that a try. BTW does the LS460 have a radiator cap? I looked all the way along the top of the rad and couldn't find one.

jmcraney

I don't know much about this so I hope that I am telling you right. That nylon tank that you refer to as the "coolant resevoir" is the equivalent of the coolant resovoir that is the upper part of more conventional radiators. And the cap on that tank is equivalent to the radiator cap that we see on older models. If your cap is missing then it is unlikely that your car can contain the coolant when it heats up. The cap is designed to provide pressurization, which increases the boiling point, for the coolant when it gets hot and prevents a vacuum when the coolant cools, just like the radiator caps of old. If your cap is missing then that will be a problem. And if some sort of cap has been substituted then that will be a problem. The cap has a definite "click" when it is correctly tightened and that is important. Just like the older radiators, you should only remove the cap when the car is cold and you should only add liquid when the car is cold.