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After driving an 05 ls430 for a few years I couldn't get over the fact that I liked the 98-00 LS400s more.. So i picked one up!
Weird problem with climate control on it though... AC works phenomenal on MAX COLD setting but once I turn the temp up even one degree to 65 the heat goes on full. Happens on auto mode and manual mode.. In other words, 65 degrees pumps out the same temp air as say, 75 degrees, which is the same hot air temp as the MAX HOT setting. Any ideas?
After driving an 05 ls430 for a few years I couldn't get over the fact that I liked the 98-00 LS400s more.. So i picked one up!
Weird problem with climate control on it though... AC works phenomenal on MAX COLD setting but once I turn the temp up even one degree to 65 the heat goes on full. Happens on auto mode and manual mode.. In other words, 65 degrees pumps out the same temp air as say, 75 degrees, which is the same hot air temp as the MAX HOT setting. Any ideas?
On the max cold setting the recirculation setting is on, IE the recirculation door is open. When you increase the temperature the recirculation door is closed unless you press recirculation again. You likely have a blend door issue that is stuck on full heat. Do the AC diag through the climate control and check for codes using an OBD2 scanner. If it is a blend door issue, likely the dash has to come out. Try to hit recirculate when the temperature is increased and see if your ac still stays cold.
I've never had to diag the HVAC system. Attached is a starting point.
The system does have a self-diagnosis function.
May point you in the right direction. Good luck.
I wanted to add the Problem Symptoms Table from the FSM - "Temperature Control : No temperature control (only Max. cool or Max. warm)" should provide suspect areas to investigate.
Getting to the blend doors and the servomotors is one hell of a job. I pulled the dash (and soooo much more) on my 93 to change the heater core, with the car half buried in snow. Wow the memories, 4 days worth of memories. I don't know too much on how the HVAC works but it sounds like the blend door is opening and closing but just at 100%, nowhere in the middle. Peacebay; I got a question for you. Where the heck do you find these nice LS400s here in Ct.? I been looking for a while and can't seem to find a good one. I've also been looking down south and still can't find a decent one.
Getting to the blend doors and the servomotors is one hell of a job. I pulled the dash (and soooo much more) on my 93 to change the heater core, with the car half buried in snow. Wow the memories, 4 days worth of memories. I don't know too much on how the HVAC works but it sounds like the blend door is opening and closing but just at 100%, nowhere in the middle. Peacebay; I got a question for you. Where the heck do you find these nice LS400s here in Ct.? I been looking for a while and can't seem to find a good one. I've also been looking down south and still can't find a decent one.
I don't pay particular attention
But nice cars come from rich areas in New England... well, the ones that aren't rusted.
On the max cold setting the recirculation setting is on, IE the recirculation door is open. When you increase the temperature the recirculation door is closed unless you press recirculation again. You likely have a blend door issue that is stuck on full heat. Do the AC diag through the climate control and check for codes using an OBD2 scanner. If it is a blend door issue, likely the dash has to come out. Try to hit recirculate when the temperature is increased and see if your ac still stays cold.
It's gotta be something along those lines, although the recirculation button does work fine on Max cold (or any other temp). AC stays cold when I turn recirculate button off. Looking like the dash needs to come out but as long as my heat and AC work I'll probably just deal with it, oh well.
Originally Posted by deanshark
Getting to the blend doors and the servomotors is one hell of a job. I pulled the dash (and soooo much more) on my 93 to change the heater core, with the car half buried in snow. Wow the memories, 4 days worth of memories. I don't know too much on how the HVAC works but it sounds like the blend door is opening and closing but just at 100%, nowhere in the middle. Peacebay; I got a question for you. Where the heck do you find these nice LS400s here in Ct.? I been looking for a while and can't seem to find a good one. I've also been looking down south and still can't find a decent one.
I looked daily for almost a year for a clean silver or black 98-00 LS400 and found this one in Rhode Island, with Florida plates on it. One owner, old woman, spent its life garaged in Florida.
Originally Posted by Sin1UZFE
Definitely the issue is those rims
OEM 18 LS430 wheels are the issue? Looking back at your post history you've started threads asking how black steelies would look on your '99.. Just gonna leave it at that
[QUOTE=Peacebay;11115716]After driving an 05 ls430 for a few years I couldn't get over the fact that I liked the 98-00 LS400s more.. So i picked one up!
Weird problem with climate control on it though... AC works phenomenal on MAX COLD setting but once I turn the temp up even one degree to 65 the heat goes on full. Happens on auto mode and manual mode.. In other words, 65 degrees pumps out the same temp air as say, 75 degrees, which is the same hot air temp as the MAX HOT setting. Any ideas? [/QUOTE}
Off-topic, but I love the fact that even though you went to the 400 side, you couldn't shake the 430 out of you totally. Those are Eurosport 18's from a 430! Nice.
Looking like the dash needs to come out but as long as my heat and AC work I'll probably just deal with it, oh well.
I looked daily for almost a year for a clean silver or black 98-00 LS400 and found this one in Rhode Island, with Florida plates on it. One owner, old woman, spent its life garaged in Florida.
That's what I would do, knowing what it takes to get the dash out. As long as it works somehow.
Congrats on finding the nice ones. What you explained; Florida, garaged, old woman, one owner, that's exactly what I'm looking for. You must have found it on the one day I didn't look.
Off-topic, but I love the fact that even though you went to the 400 side, you couldn't shake the 430 out of you totally. Those are Eurosport 18's from a 430! Nice.
Haha, I was worried how it would ride after the stock 16s that came on it but the Vredstein Quatracs are AMAZING
Originally Posted by deanshark
That's what I would do, knowing what it takes to get the dash out. As long as it works somehow.
Congrats on finding the nice ones. What you explained; Florida, garaged, old woman, one owner, that's exactly what I'm looking for. You must have found it on the one day I didn't look.
I literally picked it up 30 min after it was posted on Craigslist. Lol
08-28-21, 05:39 PM
99 LS400 climate control issue
I don't know too much on how the HVAC works but it sounds like the blend door is opening and closing but just at 100%, nowhere in the middle.
