LS400 1st gen: heater not working
10-09-17, 02:35 PM
#1
Pole Position
Thread Starter
LS400 1st gen: heater not working
My heater went out recently. I can use my AC for cold air, however I can't get any hot air whatsoever! Whether I have the AC on or not, i cannot get any hot or even warm air. I have plenty of pink coolant in the radiator so that is not a issue. Does this look like a heater core issue or am i missing something?
10-10-17, 04:25 PM
#2
Lexus Champion
My heater went out recently. I can use my AC for cold air, however I can't get any hot air whatsoever! Whether I have the AC on or not, i cannot get any hot or even warm air. I have plenty of pink coolant in the radiator so that is not a issue. Does this look like a heater core issue or am i missing something?
Check that cable to water control valve (on upper middle firewall) moves when heat is turned on...
10-10-17, 04:27 PM
#3
Lexus Champion
My heater went out recently. I can use my AC for cold air, however I can't get any hot air whatsoever! Whether I have the AC on or not, i cannot get any hot or even warm air. I have plenty of pink coolant in the radiator so that is not a issue. Does this look like a heater core issue or am i missing something?
Check that cable to water control valve (on upper middle firewall) moves when heat is turned on...
10-10-17, 04:50 PM
#4
Pole Position
Thread Starter
10-10-17, 04:52 PM
#5
Pole Position
Thread Starter
10-10-17, 05:16 PM
#6
Lexus Champion
Perhaps this is your problem?? LOL
Replace your water control valve all related preformed coolant, hoses and hose clamps...use OEM Lexus.
Be careful.when removing hoses connecting to firewall through-hole fittings...score the hose in several places to ease hose removal and avoid wrenching fittings.
Replace your water control valve all related preformed coolant, hoses and hose clamps...use OEM Lexus.
Be careful.when removing hoses connecting to firewall through-hole fittings...score the hose in several places to ease hose removal and avoid wrenching fittings.
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10-11-17, 04:02 AM
#8
Lexus Champion
This appears to be hard well water (high mineral content )build-up as a result of using tap water, and not distilled water, in the cooling system..
It should probably be professionally cleaned and flushed BEFORE next timing belt-water pump service.
Replaced a water control valve on a 1993 LS400.
which was experiencing an elusive slow coolant leak...
Zero build-up, so the only way I was able to confirm this was tte source of the leak was to wrap a paper towel around the valve and wait for coolant stains to sppear...and they did...problem solved..
Due to mileage and age of internal rubber seals, probably a majority of water control valves on 1990-1994 LS400's should be inspected for leakss.
Last edited by YODAONE; 10-11-17 at 04:17 AM.
10-11-17, 11:46 AM
#9
Pole Position
Thread Starter
10-11-17, 11:49 AM
#10
Pole Position
Thread Starter
Corrosion??
This appears to be hard well water (high mineral content )build-up as a result of using tap water, and not distilled water, in the cooling system..
It should probably be professionally cleaned and flushed BEFORE next timing belt-water pump service.
Replaced a water control valve on a 1993 LS400.
which was experiencing an elusive slow coolant leak...
Zero build-up, so the only way I was able to confirm this was tte source of the leak was to wrap a paper towel around the valve and wait for coolant stains to sppear...and they did...problem solved..
Due to mileage and age of internal rubber seals, probably a majority of water control valves on 1990-1994 LS400's should be inspected for leakss.
This appears to be hard well water (high mineral content )build-up as a result of using tap water, and not distilled water, in the cooling system..
It should probably be professionally cleaned and flushed BEFORE next timing belt-water pump service.
Replaced a water control valve on a 1993 LS400.
which was experiencing an elusive slow coolant leak...
Zero build-up, so the only way I was able to confirm this was tte source of the leak was to wrap a paper towel around the valve and wait for coolant stains to sppear...and they did...problem solved..
Due to mileage and age of internal rubber seals, probably a majority of water control valves on 1990-1994 LS400's should be inspected for leakss.
10-11-17, 04:07 PM
#11
Pole Position
Thread Starter
My heater went out recently. I can use my AC for cold air, however I can't get any hot air whatsoever! Whether I have the AC on or not, i cannot get any hot or even warm air. I have plenty of pink coolant in the radiator so that is not a issue. Does this look like a heater core issue or am i missing something?
Perhaps this is your problem?? LOL
Replace your water control valve all related preformed coolant, hoses and hose clamps...use OEM Lexus.
Be careful.when removing hoses connecting to firewall through-hole fittings...score the hose in several places to ease hose removal and avoid wrenching fittings.
Replace your water control valve all related preformed coolant, hoses and hose clamps...use OEM Lexus.
Be careful.when removing hoses connecting to firewall through-hole fittings...score the hose in several places to ease hose removal and avoid wrenching fittings.
10-11-17, 06:19 PM
#12
Lexus Champion
10-11-17, 07:07 PM
#13
Pole Position
Thread Starter
10-19-17, 11:13 AM
#14
Pole Position
Thread Starter
10-19-17, 11:25 AM
#15
Pole Position
Thread Starter
A issue has arose.....the valve will CLOSE when i turn it to COLD but when i turn it to HOT it stays CLOSED. I can manually OPEN it though. Mechanic says i can open it during winter for hot air or close it in summer for cold air. My question is.... is anyone familiar with what is going on now?....LOL