Trying to get heater to work.
Thread Starter
Joined: Jan 2009
Posts: 539
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From: Texas
Car: 1991 Trans Am GTA
Engine: 350 tpi
Transmission: 700R4
Axle/Gears: 3.42
Trying to get heater to work.
So i bought my 87 iroc almost a yr ago...the guy i bought it from took the air conditioner out..but left all the heater stuff in there....so i decided to try and start it...well i turned on thw switch and nothing so first i tried to see if the blower motor works...so i ran 2 wires from the battery and it kicked on...so i know that works...but when i try to turn it on from the inside nothing at all happens i checked the thick purple wire to the blower motor and its getting power...what should i check next? any help would be great i at least wanna have a heater
Member
iTrader: (4)
Joined: May 2006
Posts: 479
Likes: 1
From: New York
Car: 1987 IROC
Engine: 350 Gm H.O
Transmission: 700r4 built
Axle/Gears: 3.42 Locker
Re: Trying to get heater to work.
I don't know if this helps but my ac delete heater box has two orange, a yellow, and one baby blue wire hooked up to it.
Thread Starter
Joined: Jan 2009
Posts: 539
Likes: 0
From: Texas
Car: 1991 Trans Am GTA
Engine: 350 tpi
Transmission: 700R4
Axle/Gears: 3.42
Re: Trying to get heater to work.
well see this guy just left all the ac things in it so it does not have a ac delete box on it it just does not have that big canister in it or no ac lines...all thats in there is that black valve for the heater
TGO Supporter
Joined: Sep 2000
Posts: 6,775
Likes: 27
From: So.west IN
Car: 87 Formula/ 00 Xtreme
Engine: TPI 305/ v6
Transmission: struggling t-5/ 4l60E
Axle/Gears: 3.08/ 3.23
Re: Trying to get heater to work.
So the heat works (coolant going to heater core, hoses get hot), it's the blower motor you can't get to work, right ?
Did you check the fuse under the dash ?
Did you check the fuse under the dash ?
Thread Starter
Joined: Jan 2009
Posts: 539
Likes: 0
From: Texas
Car: 1991 Trans Am GTA
Engine: 350 tpi
Transmission: 700R4
Axle/Gears: 3.42
Re: Trying to get heater to work.
well im going based on previous owner he said he never had a problem with it....if u mean the hoses going from the heater valve in the engine bay then yes thy get hot and send water to core....but i checked the thick purple wire going to the blower motor and it has power....but does the ac have anything to do with the heat cause the previous owner totally took everything out that went with the ac
Thread Starter
Joined: Jan 2009
Posts: 539
Likes: 0
From: Texas
Car: 1991 Trans Am GTA
Engine: 350 tpi
Transmission: 700R4
Axle/Gears: 3.42
Re: Trying to get heater to work.
and there is a fuse under the dash?? not the fuses on the driver side?
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iTrader: (4)
Joined: Feb 2009
Posts: 588
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From: Camdenton, Mo/ St. Joseph, Mo
Car: 97 Cummins 92 CamaroZ28, 94 GSXR750
Engine: Modded 5.9 , carbed sbc358, modded
Transmission: Nv4500, 700R4 (for now)
Axle/Gears: stock
Re: Trying to get heater to work.
If your blower motor is out Ive got one that ill sell u 30 shipped. I got it and then found out i just a hole in one of my vaccumn lines so it wasnt blowin. PM me if u need it
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TGO Supporter
Joined: Sep 2000
Posts: 6,775
Likes: 27
From: So.west IN
Car: 87 Formula/ 00 Xtreme
Engine: TPI 305/ v6
Transmission: struggling t-5/ 4l60E
Axle/Gears: 3.08/ 3.23
Re: Trying to get heater to work.
This supplies power to the fan switch on the HVAC controls for the 3 low speeds (+12 goes to resistor pack on the top of the blower box), and power that makes the high speed blower relay switch for direct battery power for high speed (I cliff-noted that, hope it makes sense)
Junior Member
Joined: Oct 2007
Posts: 48
Likes: 1
From: Kansas
Car: 90 Trans Am
Engine: 5.0 TPI- slightly modified...
Transmission: Modified 700-R4
Axle/Gears: 10 bolt 3.23 eaton posi moser shaft
Re: Trying to get heater to work.
So i bought my 87 iroc almost a yr ago...the guy i bought it from took the air conditioner out..but left all the heater stuff in there....so i decided to try and start it...well i turned on thw switch and nothing so first i tried to see if the blower motor works...so i ran 2 wires from the battery and it kicked on...so i know that works...but when i try to turn it on from the inside nothing at all happens i checked the thick purple wire to the blower motor and its getting power...what should i check next? any help would be great i at least wanna have a heater
Check the purple wire at the blower motor, if you have 12V and the motor works from external power, then you have a ground issue. Check the Black wire for continuity through a known good ground.
If you do not have a good ground, then the first stop to check is the rear of the passesger side head. The blower motor grounds here, alond with alot of other components. Make sure that the wire is connected and not corroded and/or damaged. If your connection is good, then you will have to trace the wire. It runs through 2 splices, (S112 which is in the harness loom directly above the blower motor housing, and either S185 or S115 depending on your motor they are in the harness loom directly above the rear passenger side of the loom) a connector- C105 is above the passenger rear valve cover, and is a 4 prong plastic connector joining 2 seperate harnesses.
Check each of these connections and repair the fault. If you don't have the patience to do all of that, just runa ground from the motor to the firewall above the blowor motor housing. Just DON'T drill into something important.
Thread Starter
Joined: Jan 2009
Posts: 539
Likes: 0
From: Texas
Car: 1991 Trans Am GTA
Engine: 350 tpi
Transmission: 700R4
Axle/Gears: 3.42
Re: Trying to get heater to work.
Thanks hotbird that really helped alot...and im getting power to the purple wire so im going to trace the ground hopefully i can fix it so i can have some heat.
Thread Starter
Joined: Jan 2009
Posts: 539
Likes: 0
From: Texas
Car: 1991 Trans Am GTA
Engine: 350 tpi
Transmission: 700R4
Axle/Gears: 3.42
Re: Trying to get heater to work.
Should be one under the dash labels htr a/c (or close to that) with a 25A fuse.
This supplies power to the fan switch on the HVAC controls for the 3 low speeds (+12 goes to resistor pack on the top of the blower box), and power that makes the high speed blower relay switch for direct battery power for high speed (I cliff-noted that, hope it makes sense)
This supplies power to the fan switch on the HVAC controls for the 3 low speeds (+12 goes to resistor pack on the top of the blower box), and power that makes the high speed blower relay switch for direct battery power for high speed (I cliff-noted that, hope it makes sense)
Junior Member
Joined: Oct 2007
Posts: 48
Likes: 1
From: Kansas
Car: 90 Trans Am
Engine: 5.0 TPI- slightly modified...
Transmission: Modified 700-R4
Axle/Gears: 10 bolt 3.23 eaton posi moser shaft
Re: Trying to get heater to work.
Anytime... I have had some of those very same frustrations. I got my car out of a cornfield in IL, I would have been smarter to part it out and start all over, but I am a glutton for punishment. I just installed a Champion 4 Core radiator... now I'm into the fun parts.
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