89 suburban
crystalg
12-02-2008, 06:11 PM
I have a 1989 GMC Suburban. The problem that I am having is the heater doesnt work very well. If the truck is in idle the heat wont blow or heat up. It will not blow or heat up until you have been driving for about 15 20 mins and it doesnt blow very hard. I have 2 kids and the back seat doesnt get very warm. What could possibly be the problem?
The other problem that I am having is only the right running tail light and brake light works fine but the left running light doesnt work and the brake light is dim. What could be that problem?
The other problem that I am having is only the right running tail light and brake light works fine but the left running light doesnt work and the brake light is dim. What could be that problem?
biggm
12-03-2008, 09:36 AM
I have a 1989 GMC Suburban. The problem that I am having is the heater doesnt work very well. If the truck is in idle the heat wont blow or heat up. It will not blow or heat up until you have been driving for about 15 20 mins and it doesnt blow very hard. I have 2 kids and the back seat doesnt get very warm. What could possibly be the problem?
The other problem that I am having is only the right running tail light and brake light works fine but the left running light doesnt work and the brake light is dim. What could be that problem?
If you have low fluid in your radiator it will not get hot in the heater core. If you have some restriction of the fluid to the heater core it will not get hot either. If your relay is not working on the fan motor for the heater core it will not turn the fan or if the fan is dragging for the heater core. If your heater vent doors are not getting the vacuum they need to open then the doors will hold the air back from coming out. If you want a quick check on this just use a can of smoke to inject into the vacuum line to see where the smoke is coming out and it may show a broken line or open line in the vacuum line system. Sometimes the valves just stick and they have to be manually opened up at first and just use some penetrating fluid sprayed on the valves in the heater system. I have also shot this into my lines to soften them some and expand the connector points as this usually will just follow the vacuum over the lines. Or, else you have a bad heater switch that is not allowing the contacts to work the valve mechanisms. If your heater fan is running slow it is a relay or bad voltage (switch or wire)in the fan or to the fan. If it is running fast after you set it on high at the switch then it is not blowing heat from the heater core due to the lack of fluid in the heater core or the air conditioner diverter valve in the evaporator-heater assembly is not opening up to the heater side but of course you should most likely instead get some rapid air movement from the vents in this case but not hot. Otherwise it is the other I said.
The lights on your rear is usually a dirty bulb contact or bad bulb most likely. The reason for this is that the series of the circuitry needs to complete a voltage requirment. I have seen bulbs that will light up but not strong enough to cause a feedback to the flasher contacts. I would try to make sure the bulbs are new, clean the contact surfaces and then make sure all of them has a ground that is good by using a meter to test the continuity. Get some new bulbs for sure where you might have one not burning. If, I can help more just ask. biggm
The other problem that I am having is only the right running tail light and brake light works fine but the left running light doesnt work and the brake light is dim. What could be that problem?
If you have low fluid in your radiator it will not get hot in the heater core. If you have some restriction of the fluid to the heater core it will not get hot either. If your relay is not working on the fan motor for the heater core it will not turn the fan or if the fan is dragging for the heater core. If your heater vent doors are not getting the vacuum they need to open then the doors will hold the air back from coming out. If you want a quick check on this just use a can of smoke to inject into the vacuum line to see where the smoke is coming out and it may show a broken line or open line in the vacuum line system. Sometimes the valves just stick and they have to be manually opened up at first and just use some penetrating fluid sprayed on the valves in the heater system. I have also shot this into my lines to soften them some and expand the connector points as this usually will just follow the vacuum over the lines. Or, else you have a bad heater switch that is not allowing the contacts to work the valve mechanisms. If your heater fan is running slow it is a relay or bad voltage (switch or wire)in the fan or to the fan. If it is running fast after you set it on high at the switch then it is not blowing heat from the heater core due to the lack of fluid in the heater core or the air conditioner diverter valve in the evaporator-heater assembly is not opening up to the heater side but of course you should most likely instead get some rapid air movement from the vents in this case but not hot. Otherwise it is the other I said.
The lights on your rear is usually a dirty bulb contact or bad bulb most likely. The reason for this is that the series of the circuitry needs to complete a voltage requirment. I have seen bulbs that will light up but not strong enough to cause a feedback to the flasher contacts. I would try to make sure the bulbs are new, clean the contact surfaces and then make sure all of them has a ground that is good by using a meter to test the continuity. Get some new bulbs for sure where you might have one not burning. If, I can help more just ask. biggm
biggm
12-03-2008, 09:39 AM
I have a 1989 GMC Suburban. The problem that I am having is the heater doesnt work very well. If the truck is in idle the heat wont blow or heat up. It will not blow or heat up until you have been driving for about 15 20 mins and it doesnt blow very hard. I have 2 kids and the back seat doesnt get very warm. What could possibly be the problem?
The other problem that I am having is only the right running tail light and brake light works fine but the left running light doesnt work and the brake light is dim. What could be that problem?I might also add that the thermostat coud be not working right.
The other problem that I am having is only the right running tail light and brake light works fine but the left running light doesnt work and the brake light is dim. What could be that problem?I might also add that the thermostat coud be not working right.
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