My crazy truck has no heat. It’s not working in the front or rear. I can’t find the cabin filter. I took it apart last night and the heater core was hot. My coolant temperature seems to be going up and the vents are working. If I change which vent I want it to come out it works. I ordered a new climate control unit last night. The one in it was used from eBay and I already had to swap out the blower switch.
2000 Denali heat
- Thread starter Rob Yukon
- Start date
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CorbinC124
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so from what i understand its not a standard cabin filter like most new cars, i believe its actually a metal one built in but i could be wrong, also it sounds like you might have a clog in your vents
Joseph Garcia
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It is either the control module, or the blender doors are out of synch.
@swathdiver may be able to provide some input and advice on this issue.
@swathdiver may be able to provide some input and advice on this issue.
See if this helps:
SilverSport
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Isn't the 2000 Denali a GMT400???...or did they switch to the GMT800 version during the 2000 model year...?
Bill
Bill
Good question. Maybe the OP will enlighten us.
swathdiver
Full Access Member
You may have a bad actuator or controller or they might simply need calibrating. Not sure on that year. Go to Charm.Li and download the shop manual for your truck and start diagnosing. It would be helpful to know if you have any internal BCM codes related to this that may point the way to the problem. A bi-directional scan tool is needed to pull them. Not sure if an IPhone with CarScanner can do it on that generation.
Show us a good pic of it.
SilverSport
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does it look like the pic of the one I attached above???...then it is a GMT400 (I believe)...Do you have a Vortec 350 or a 5.3/6.0 engine???...if it is the 350 it should be a GMT400...1999 and 2000 in the Escalade were GMT400s...
...Bill
...Bill
strutaeng
Full Access Member
2000 Denali is GMT400 or "OBS" with a 5.7 SBC Vortec. No cabin filter.
If it looks like the body style of @SilverSport or @Fless Avatar's, then it's a GMT800 or "NBS" with a 5.3 or 6.0 Vortec which is actually LS-based engines. Does have cabin filters on the 00-02 generation.
Given what you have said, I would try taking readings of the heater hoses going into the cabin with an IR thermometer, or just simply touch the lines using caution. One should be pretty hot, and the other less. If both are hot, that means the heat exchanging is not occurring inside the cab. Figure out why. Or there's coolant flow issues. If neither are hot, then may have coolant flow issues also (pump not circulating hot coolant through the lines).
On the LS-based engines, they are designed with the little crossover pipes that pretty much self bleed if you open up the coolant system. However, on the SBC, you can trap air pockets and you have do some strange thigs like raising the front of the engine or something like that. They sell a funnel with adapters that screw into the radiator cap. Had to do it on my beater K3500 SBC when I replaced the radiator. I've never had to use it on the LS engines. Just run the heater full blast and flip the throttle a few times with the cap off and that's it: you'll see air bubbles coming up on the reservoir tank.
You haven't replaced a water pump, radiator or thermostat, have you? Or what is the history with the truck? You just bought it? Or was the heater working well at some point and then it stopped working?
If it looks like the body style of @SilverSport or @Fless Avatar's, then it's a GMT800 or "NBS" with a 5.3 or 6.0 Vortec which is actually LS-based engines. Does have cabin filters on the 00-02 generation.
Given what you have said, I would try taking readings of the heater hoses going into the cabin with an IR thermometer, or just simply touch the lines using caution. One should be pretty hot, and the other less. If both are hot, that means the heat exchanging is not occurring inside the cab. Figure out why. Or there's coolant flow issues. If neither are hot, then may have coolant flow issues also (pump not circulating hot coolant through the lines).
On the LS-based engines, they are designed with the little crossover pipes that pretty much self bleed if you open up the coolant system. However, on the SBC, you can trap air pockets and you have do some strange thigs like raising the front of the engine or something like that. They sell a funnel with adapters that screw into the radiator cap. Had to do it on my beater K3500 SBC when I replaced the radiator. I've never had to use it on the LS engines. Just run the heater full blast and flip the throttle a few times with the cap off and that's it: you'll see air bubbles coming up on the reservoir tank.
You haven't replaced a water pump, radiator or thermostat, have you? Or what is the history with the truck? You just bought it? Or was the heater working well at some point and then it stopped working?
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