LOST JEEPS :: View topic - No cab heat or defrost

I have a 2005 Liberty Diesel. Over the last year and half I have replaced the following, heater core, thermostat, turbo, water pump, and added a switch for the auxiliary vicous (sp) heater (mechanic said the pcm was not telling it to turn on). Mechanic checked all control doors on the heater and I am still not getting heat in cab. AC is working great. I just got this back from the mechanic could there be an air pocket in water lines? The heater lines are hot after vehicle runs for awhile. I am stumped. Thanks for any help

Kelly

Author:	Browningcollector [ Tue May 30, 2017 9:43 am ]
Post subject:	No cab heat or defrost
I have a 2005 Liberty Diesel. Over the last year and half I have replaced the following, heater core, thermostat, turbo, water pump, and added a switch for the auxiliary vicous (sp) heater (mechanic said the pcm was not telling it to turn on). Mechanic checked all control doors on the heater and I am still not getting heat in cab. AC is working great. I just got this back from the mechanic could there be an air pocket in water lines? The heater lines are hot after vehicle runs for awhile. I am stumped. Thanks for any help Kelly

Author:	papaindigo [ Tue May 30, 2017 10:01 am ]
Post subject:	Re: No cab heat or defrost
If both heater core lines are hot and about the same degree of hot then coolant is going into/out of the heater core. There is no "valve" controlling heater core coolant flow rather the amount of heat in the cabin is controlled by the HVAC "hot/cold" switch on the dash which controls "blend" doors inside the HVAC system. Your mechanic's opinion notwithstanding the only reason I can see for not getting heat, with both heater core lines hot, is a blend door malfunction. If the 2 heater lines are not close to the same in temp it's possible the heater core is clogged. It can be reverse flushed; undo both lines; gently back flush core with a hose using the "outflow" line (not the viscous heater line). I have no clue why you added a viscous heater switch. If it's not turning on it could be 1) bad relay; 2) bad temp signal to PCM/ECM, whichever controls on/off; 3) bad electric circuit (ex. bad ground); or 4) viscous clutch shot. In any case the viscous heater is a non-essential component that doesn't do anything but provide minimal extra heat during warm up; not worth it in hot climes and only minimal help in cold ones.

Author:	flash7210 [ Tue May 30, 2017 10:40 am ]
Post subject:	Re: No cab heat or defrost
Browningcollector wrote: I have a 2005 Liberty Diesel. Over the last year and half I have replaced the following, heater core, thermostat, turbo, water pump, and added a switch for the auxiliary vicous (sp) heater (mechanic said the pcm was not telling it to turn on). Mechanic checked all control doors on the heater and I am still not getting heat in cab. AC is working great. I just got this back from the mechanic could there be an air pocket in water lines? The heater lines are hot after vehicle runs for awhile. I am stumped. Thanks for any help Kelly What is your actual coolant temperature? Is the temp gauge needle getting up near the 12:00 position? Is it getting up above 1/4 on the gauge? If the coolant is getting up to proper temperature, then the only possibilities are a clogged heater core or a bad air-blend door.

Author:	Browningcollector [ Tue May 30, 2017 10:52 am ]
Post subject:	Re: No cab heat or defrost
Temp gauge reading OK. I will attempt to flush the core, but it was put in new recently Kelly

Author:	flash7210 [ Tue May 30, 2017 10:56 am ]
Post subject:	Re: No cab heat or defrost
Browningcollector wrote: Temp gauge reading OK. I will attempt to flush the core, but it was put in new recently Kelly Maybe whoever put in the new heater core didnt connect the linkage or whatever to the blend door? highlighted in purple

LOST JEEPS http://www.lostjeeps.com/forum/phpBB3/

No cab heat or defrost http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=86639	Page 1 of 1

Author:	papaindigo [ Tue May 30, 2017 11:30 am ]
Post subject:	Re: No cab heat or defrost
If heater core is new and both hoses are about the same temp, feel is close enough, then I'd bet on blend door problem.

Author:	WWDiesel [ Tue May 30, 2017 2:01 pm ]
Post subject:	Re: No cab heat or defrost
Also could be the selector switch not sending a signal to the blend door actuator?

Author:	flash7210 [ Tue May 30, 2017 2:09 pm ]
Post subject:	Re: No cab heat or defrost
WWDiesel wrote: Also could be the selector switch not sending a signal to the blend door actuator? Good point. This pic is the back side of the HVAC controls. Item #3 is the connector for the blend door control.

Page 1 of 1	All times are UTC - 5 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/