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Discussion Starter #1
I got into an accident last week and my radiator support, radiator, ac condensor was damaged. I replaced everything and bought a brand new thermostat from toyota at the same time I put it all back together and bled the coolant maybe 5 times and I get no heat. My car gets to its operating temperature and stays there and does not overheat but I have no heat. The only thing I can think is wrong is I got a defective thermostat or maybe I put it in wrong. I put the spring side in towards the block. I do notice my lower radiator hose does get slightly hot. I believe one hose is supposed to stay cool but I forgot which. Can someone shed some light on this problem?
 

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Yea, your lower hose is the coldest spot in the system and will stay cold to the touch for about 10-15 minutes roughly, when the thermostat opens there's a noticeable change. How did you bleed the coolant, with the rad cap off and with a radiator funnel? That is the only way to go because fsm's method of keeping it sealed takes a lot of time. I think you have air still trapped especially in your core, so I suggest using a funnel($20), the alternate is draining a little over a quart of coolant from the rad drain and run it.
I didn't think it was possible to put the thermostat in wrong but I know that gasket has to be good.
BTW, I've heard of OE Toyota boxed thermostats going bad right out of the box so thermostat failure isn't completely out of the question. I just think you still have air in there, especially if the fans never come on(which takes a long time to do at idle on cold startup).
 

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Discussion Starter #3
Also my fans do not come on when I am bleeding but they do come on when I turn on the ac so I know they are not broken.
 

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Is the radiator completely full of coolant, mainly when the engine is very cold? Half full cold in the reservoir too? Did you see any air bubbles comes out and did you squeeze the hoses when bleeding? The trouble with doing it with just the rad cap off is that the coolant will simply boil over and completely spray the bay, you can keep the level about 2" low below the neck and bleed it, I've done that. But when it cools it will contract and you have to leave the cap off then fill it completely when it's cold.
 

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Discussion Starter #6
yeah, its completely fill. i just checked the fsm and it says Align the jiggle valve of the thermostat with the protrusion of the water inlet. I didnt do that. someone told me the valve has to be aligned and pointed upwards to allow it to properly bleed. I think ill drain my radiator, take out the thermostat and align it according to the fsm and then buy the funnel and bleed it.
 

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I honestly didn't know there was a way to screw up the thermostat besides messing up the gasket. Spring side or body of the thermostat goes towards the block I believe. Run your car then let it cool and I bet the radiator is not completely filled to very top of the neck

Btw, the temperature of the coolant is the same as what's in the block because the water for the core comes from the back of the water pump so naturally the heat changes as the block warms rather then when the thermostat opens. That's why I still think you have air trapped and maybe causing more than one problem.
 

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Discussion Starter #8
i didn't know there was more than one way to mess it up either, but according to the fsm i guess there is. i went ahead and took out the new thermostat to compare it to my old one and found this difference.

my new oem one:


you can see the "jiggle valve" the fsm refers to.

my old thermostat:


i bought the car with this one and apparently it is aftermarket. i dont see a "jiggle valve" on it.

fsm instructions on installing it:


i will install it according to the fsm and try to bleed it again and report back. thank you for all the help so far btw. I really appreciate it!
 

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Discussion Starter #9
I got that problem fixed and my car running again. Thank you once again Jason! My abs/traction/brake light is on. I believe my front passenger abs sensor might be damaged. I will get it scanned tomorrow. Does anyone know if a broken abs sensor would also cause the brake light to come on?
 

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Glad to hear you got the heat working, also glad I could help.

A damaged wheel sensor would throw the ABS light but not brake. You can even check them with an ohmmeter, fronts read 1600 ohms while rears are about 1000 ohms. The BRAKE indicator is caused by either the handbrake is engaged or the float in the brake fluid reservoir is detecting low fluid, sometimes it can get stuck. To check to see if that's it, simply disconnect the connector and cycle the ignition to see if it goes out. Like the parking switch it closes to ground when the float is down. However, an active ABS fault can set the "BRAKE" indicator.
 

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I got that problem fixed and my car running again. Thank you once again Jason! My abs/traction/brake light is on. I believe my front passenger abs sensor might be damaged. I will get it scanned tomorrow. Does anyone know if a broken abs sensor would also cause the brake light to come on?
Maybe you'll get lucky and it will just need to be cleaned and installed correctly. Had that issue on mine last month.
 

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Discussion Starter #12
well, this all started after my car was in a front end collision so i think the wire might be stretched or damaged. i will try to clean and reinstall it again though. i unplugged the sensor from the brake fluid reservoir and started the car and the brake light was still on. my e brake is also fully down. what should i check next?
 

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well, this all started after my car was in a front end collision so i think the wire might be stretched or damaged. i will try to clean and reinstall it again though. i unplugged the sensor from the brake fluid reservoir and started the car and the brake light was still on. my e brake is also fully down. what should i check next?
It may be the parking brake switch or because you have a ABS fault. The complete diagnostic for the BRAKE light is on page #711 or DI-490. Here's a link I'll leave up for a bit in case you don't have it. It says an issue with the skid module can set the BRAKE light as well a few pages back.
https://www.dropbox.com/s/nji5xr398lz7mio/2001-05 IS300 Diagnostic & Wiring & TSB Manual.pdf
 
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