1989 C4 HVAC Blower Motor/Fan No Higher Speeds
12-16-2017, 08:05 PM
#1
1989 C4 HVAC Blower Motor/Fan No Higher Speeds
1989 C4 Corvette
HVAC Climate Control;
1) BLOWER Fan Speed only works up to “07”
2) Only 10 volts max at blower motor on setting 07, 08, 09 & 10, when less than “07” setting then less volts.
3) When direct battery voltage 12v is jumped to blower motor it runs faster.
4) On the older cars there is a High Fan (blower) Relay. So, is there 1 on this model? and if so, where located?
5) Blower only comes on after key is on for 30 seconds, I do not recall if this is normal or not, is it?
So any ideas on what is wrong? and possible solutions?
HVAC Climate Control;
1) BLOWER Fan Speed only works up to “07”
2) Only 10 volts max at blower motor on setting 07, 08, 09 & 10, when less than “07” setting then less volts.
3) When direct battery voltage 12v is jumped to blower motor it runs faster.
4) On the older cars there is a High Fan (blower) Relay. So, is there 1 on this model? and if so, where located?
5) Blower only comes on after key is on for 30 seconds, I do not recall if this is normal or not, is it?
So any ideas on what is wrong? and possible solutions?
12-16-2017, 08:58 PM
#2
Melting Slicks
IF you have the C68 Electronic HVAC control, there is a "blower motor control/resistor" that sits on top of the blower housing. On both my 91 and 92 it's passenger side in the engine bay and sits right on top where it's easy to get to.
If you can get ahold of an FSM there's some checks that can be done to isolate the problem without throwing parts at it. I don't have an 89 FSM, so not sure mine will be exactly the same for yours ( I presume so, but I'm not an expert on what all the changes are year-to-year.)
Anyway, that's the part that was bad on my 91, and it started the same way... not blowing as hard as it should. Then one night it started again, but wouldn't shut off! I had to pull the fuse to keep it from running all night.
Odd thing is, since they're the same on both of mine, I swapped them. It fixed my '91 and didn't behave bad on the 92...
Rock auto has them. I'd imagine other places do as well.
ACDELCO 1571642 {#12368387, 16086891} GM Original Equipment
If you can get ahold of an FSM there's some checks that can be done to isolate the problem without throwing parts at it. I don't have an 89 FSM, so not sure mine will be exactly the same for yours ( I presume so, but I'm not an expert on what all the changes are year-to-year.)
Anyway, that's the part that was bad on my 91, and it started the same way... not blowing as hard as it should. Then one night it started again, but wouldn't shut off! I had to pull the fuse to keep it from running all night.
Odd thing is, since they're the same on both of mine, I swapped them. It fixed my '91 and didn't behave bad on the 92...
Rock auto has them. I'd imagine other places do as well.
ACDELCO 1571642 {#12368387, 16086891} GM Original Equipment
12-16-2017, 10:45 PM
#3
yes it is "climate control' electronic.
i know about that part, was not sure if it controls high blower speed too, as on my older cars there is a resistor series for lower speeds and high is a relay.
If it is that $150+ part, i may just rig up a relay and a toggle switch for when i need highest setting.
i'll have to dig my manuals out of storage i guess, was hoping someone had such info.
i know about that part, was not sure if it controls high blower speed too, as on my older cars there is a resistor series for lower speeds and high is a relay.
If it is that $150+ part, i may just rig up a relay and a toggle switch for when i need highest setting.
i'll have to dig my manuals out of storage i guess, was hoping someone had such info.
The following users liked this post:
1982Stingray (12-17-2017)
12-17-2017, 01:37 PM
#6
and pick-n-pulls are few and far between and have mostly import crap i've never seen a 80's-90's Cadillac or Buick at one.If you come across another i'd pay for your time to mail 1 to me.
I'm not in a hurry, i think i'll wire in a relay & switch until i get a replacement.
12-31-2017, 03:01 PM
#7
surprised not much feedback on this problem
1989 C4 Corvette
HVAC Climate Control;
1) BLOWER Fan Speed only works up to “07”
2) Only 10 volts max at blower motor on setting 07, 08, 09 & 10, when less than “07” setting then less volts.
3) When direct battery voltage 12v is jumped to blower motor it runs faster.
4) On the older cars there is a High Fan (blower) Relay. So, is there 1 on this model? and if so, where located?
5) Blower only comes on after key is on for 30 seconds, I do not recall if this is normal or not, is it?
So any ideas on what is wrong? and possible solutions?
HVAC Climate Control;
1) BLOWER Fan Speed only works up to “07”
2) Only 10 volts max at blower motor on setting 07, 08, 09 & 10, when less than “07” setting then less volts.
3) When direct battery voltage 12v is jumped to blower motor it runs faster.
4) On the older cars there is a High Fan (blower) Relay. So, is there 1 on this model? and if so, where located?
5) Blower only comes on after key is on for 30 seconds, I do not recall if this is normal or not, is it?
So any ideas on what is wrong? and possible solutions?
12-31-2017, 03:52 PM
#8
Zen Vet Master Level VII
1982 (I had an 82 before my C4s),
Hop on Craigs List and search for a fellow parting out a C4. The part will probably work and will be comparatively cheap (I bet you can get one for $25) and an easy swap.
BTW... your symptoms mean the resistor is at fault. Swap and smile!
Hop on Craigs List and search for a fellow parting out a C4. The part will probably work and will be comparatively cheap (I bet you can get one for $25) and an easy swap.
BTW... your symptoms mean the resistor is at fault. Swap and smile!
12-31-2017, 04:14 PM
#9
OP - The FSM has a rather straight forward diagnostic for your situation. You need the FSM.
12-31-2017, 07:38 PM
#10
Race Director
