Purchased my first LC 100, 2003 model, last year around the beginning of winter here in Florida. Early mornings got cold and I might have turned the heat on twice. When I had the heat set on full blast it was blowing cool air and never got hot. I didn't think it was a big deal at the time as it started to warm up. Recently I turned the heat on again and still out. I am now getting ready for a trip north over Christmas. This time the wife and sister in law will need to be warm or I will hear it the entire trip. Has anyone else experienced this issue? I have looked to try and find a solution but no luck. I haven't checked the thermostat, yet. I would like to see if anyone else has has a possible solution before I go to a shop to have it diagnosed.
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
arcteryx
Supporting Vendor
Swap in a new tstat, cheap insurance. Does your rear heater work?
Run a search for temperature control sensor. There are 2, one inside near your right knee and one outside under the right front bumper. Others have had problems with those causing odd symptoms with the HVAC and have posted threads about it. Even with an open thermostat, the engine gets hot enough to provide at least some heat. So, if you have no heat at all, it seems more likely to be a sensor?
- Thread starter
- #5
Nothing seems to be working in the rear. No heat or air flow. I have had some issues recently where the rear air will inadvertently turn on.
I will do a search and see what I come up with. This could explain the fact that the air flow temp changes from ambient temperature to slightly cool.
That was recently topped and is on par.
Check the coolant lines on your firewall to make sure they are not looped to bypass a leaky heater core.
Heater core has been my issue though my symptoms are a little different in that I get heat in the rear. Heater core is cheap, replacement looks like something not so cheap. Thankfully it's been warm so far...
Interesting. Why & How much coolant did it need to top off?
arcteryx
Supporting Vendor
I thought the same thing when I read that. This could be something to be concerned about. Have you checked the color or your oil or smelled your exhaust for coolant? I am not aware of head gaskets being an issues on these engines like the 1FZ/3F/2Fs but it is possible. Also, does your temp gauge fluctuate or is it constant?
I'll post this before you answer, as coolant level is most common reason. Bad or improperly installed thermostat (jiggle value on top is correct orientation) is second most.
Check coolant when engine cold (12hr minimum cool down). Top off to the neck of radiator & cold mark of overfull reservoir each morning (may take three or more days). When engine hot you should see temp gauge at or above center mark & reservoir level near or at hot mark.
Test radiator cap.
Check weep hole at bottom of timing chain cover for signs of coolant leak.
Check coolant lines & thermostat housings for leaks and don't forget those heater line T's (back of engine near fire wall).
Tip: Use only Toyota supplied coolant, and demineralized water when 50/50 mix is appropriate. Always flush coolant at factory recommended intervals. Do not mix other coolant brands, flush if have used or unknown. Mixing non Toyota or heavy mineral water increase chances of silicates (mineral) build up which plugs cooling system and reduce life of water pump & thermostat.
Check coolant when engine cold (12hr minimum cool down). Top off to the neck of radiator & cold mark of overfull reservoir each morning (may take three or more days). When engine hot you should see temp gauge at or above center mark & reservoir level near or at hot mark.
Test radiator cap.
Check weep hole at bottom of timing chain cover for signs of coolant leak.
Check coolant lines & thermostat housings for leaks and don't forget those heater line T's (back of engine near fire wall).
Tip: Use only Toyota supplied coolant, and demineralized water when 50/50 mix is appropriate. Always flush coolant at factory recommended intervals. Do not mix other coolant brands, flush if have used or unknown. Mixing non Toyota or heavy mineral water increase chances of silicates (mineral) build up which plugs cooling system and reduce life of water pump & thermostat.
Last edited:
Check the temp sensor behind close to the ignition, often the hose falls off. Also the flapper valve on the passenger left foot side sometimes fails to open and close. At least on my 04 was...good luck.
Sent from my VS986
Sent from my VS986
Hi Matt, I think I have the same problem you have. About a year ago I replaced my radiator (it was leaking at the tank seam) and while I was into it, I did a fresh water flush, replaced the thermostat, belts, hoses, and refilled with fresh coolant. It seemed to take a couple days to get all the air out of the system and the coolant level has been stable ever since. Last weekend I turned on the heater and the front vents blew luke warm air. Rear vents weren’t hot either and didn’t feel much air flow. Next thing I want to confirm is put my hands on the heater hoses and make sure they’re hot, the ones that run to the rear as well. If they are hot, I’m going to try to find the temp sensor and check the flapper mentioned above. If you fix yours, please post back. Thanks.
This is what I was searching for. I have the same issue: Rear heat works well, no heat in the front. Did you find a fix?
Hello,
I've had water issues with my truck. Bought it in May 2017. Its a 2001 LC100. First issues were bad sunroof and windshield install. had both sealed up and fixed. Now I have damp passenger side footwell. And I blotted the wet areas with white paper towels and the liquid was orange and brown. Leads me to think it might be leaking heater core? Let me know your thoughts and what the process for repair is?
Will attach photos below.
I've had water issues with my truck. Bought it in May 2017. Its a 2001 LC100. First issues were bad sunroof and windshield install. had both sealed up and fixed. Now I have damp passenger side footwell. And I blotted the wet areas with white paper towels and the liquid was orange and brown. Leads me to think it might be leaking heater core? Let me know your thoughts and what the process for repair is?
Will attach photos below.
Need more info "CLUES"
First is your coolant level low or declining with wetness?. Proper way to check coolant level is in the morning after a 8 hour cool down. Check under radiator cap, make sure is fill to neck, then check reservoir filling to low line plus a tad depending on outside temperature. Note: outside temperature will change level as coolant is very susceptible to heat expansion and contraction. Old use Toyota Red and Distilled water at a 50/50 mix. Is your cabin heater working and blow very hot not just warm? Clues!
Second you say fixed but how was it done. We've a serious issue with rust around windshield from improperly installation. Also holes in "A" for same reason. Look for clues like rust or paint bubbling around windshield or wind sound from air entry.
Third there are drain plugs in sunroof area, have you check to see if the drain flows. Again who fixed and what did they do.
First is your coolant level low or declining with wetness?. Proper way to check coolant level is in the morning after a 8 hour cool down. Check under radiator cap, make sure is fill to neck, then check reservoir filling to low line plus a tad depending on outside temperature. Note: outside temperature will change level as coolant is very susceptible to heat expansion and contraction. Old use Toyota Red and Distilled water at a 50/50 mix. Is your cabin heater working and blow very hot not just warm? Clues!
Second you say fixed but how was it done. We've a serious issue with rust around windshield from improperly installation. Also holes in "A" for same reason. Look for clues like rust or paint bubbling around windshield or wind sound from air entry.
Third there are drain plugs in sunroof area, have you check to see if the drain flows. Again who fixed and what did they do.
Does the interior or the paper towels smell like antifreeze? If its leaking bad enough to soak the paper towels, it should smell strong inside.
Yes.
There was a small opening in the silicone windshield seal. Water trickled down piller and into passenger floor area. Had to remove side molding and plug hole. I think it’s good now. Two days no leaking so far
