So your air vent blower motor doesn't work on high....pics
08-17-2007, 05:19 AM
#1
Melting Slicks
Thread Starter
So your air vent blower motor doesn't work on high....pics
Just fixed the blower in my '73. It would not work on high, now it does. This is the most likely cause for it not working on high, only.
Here is the resistor pack, pass. side air chamber. The fan uses one res. for off, a second one for low, both for medium and a bypass relay (next pic) for High.
The resistors reside in the air flow area. Good idea actually. GM is good for that.
Here is the blower relay. The green wire goes hot (+12V) on the switch selecting "High" & key "On". there is a seperate Blk Gnd wire towords the back of the relay you can't see in the pic. Individual hook up.
The relay shorts the Org wire (Full +12V) to the Purple wire (blower motor power wire) after the resistor pack, for full power. No problem with a common Batt.
Test yours by unpluging the 3 wire plug at the bottom of the relay. With the black lead of your DVM to a good gnd source, The green wire should go to +12V with the Key ON and the switch in the High position, only. If that's ok, check the Orange lead. It should be +12V all the time. If it's not, time for a repair.
The Org wire gets it's power from the + junction of power wires at the Horn relay stud, drivers side, midway up. the Org wire is fused near the power junction. The blower motor draws about 7 amps running on High. This is most likely the problem.
Note the rust
Time to replace it. Radio Shack can be very handy.
Cut it out, strip back about 3/16 of an in, each side, and crimp in Yellow butt splices.
Ready for the New fuse holder. Use a 20A fuse. You must use a fuse holder with 12 Gauge or greater wire attatched, 10 gauge prefered. the current runs about 12amps on high.
Here we are all crimped in with some heat shrink too. Crimp HARD. test by pulling slightly on the wires.
Heat shrink them or wrap them in two layers of good electrical tape.
Here we go. all neatly done,, and, the best part, the Blower motor works on High again!
Here is the resistor pack, pass. side air chamber. The fan uses one res. for off, a second one for low, both for medium and a bypass relay (next pic) for High.
The resistors reside in the air flow area. Good idea actually. GM is good for that.
Here is the blower relay. The green wire goes hot (+12V) on the switch selecting "High" & key "On". there is a seperate Blk Gnd wire towords the back of the relay you can't see in the pic. Individual hook up.
The relay shorts the Org wire (Full +12V) to the Purple wire (blower motor power wire) after the resistor pack, for full power. No problem with a common Batt.
Test yours by unpluging the 3 wire plug at the bottom of the relay. With the black lead of your DVM to a good gnd source, The green wire should go to +12V with the Key ON and the switch in the High position, only. If that's ok, check the Orange lead. It should be +12V all the time. If it's not, time for a repair.
The Org wire gets it's power from the + junction of power wires at the Horn relay stud, drivers side, midway up. the Org wire is fused near the power junction. The blower motor draws about 7 amps running on High. This is most likely the problem.
Note the rust
Time to replace it. Radio Shack can be very handy.
Cut it out, strip back about 3/16 of an in, each side, and crimp in Yellow butt splices.
Ready for the New fuse holder. Use a 20A fuse. You must use a fuse holder with 12 Gauge or greater wire attatched, 10 gauge prefered. the current runs about 12amps on high.
Here we are all crimped in with some heat shrink too. Crimp HARD. test by pulling slightly on the wires.
Heat shrink them or wrap them in two layers of good electrical tape.
Here we go. all neatly done,, and, the best part, the Blower motor works on High again!
Last edited by RunningMan373; 09-22-2007 at 02:49 AM.
08-17-2007, 06:40 AM
#3
Melting Slicks
Thread Starter
08-19-2007, 11:36 PM
#8
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02-20-2009, 12:16 PM
#9
Instructor
Just fixed the blower in my '73. It would not work on high, now it does. This is the most likely cause for it not working on high, only.
Here is the resistor pack, pass. side air chamber. The fan uses one res. for off, a second one for low, both for medium and a bypass relay (next pic) for High.
The resistors reside in the air flow area. Good idea actually. GM is good for that.
Here is the blower relay. The green wire goes hot (+12V) on the switch selecting "High" & key "On". there is a seperate Blk Gnd wire towords the back of the relay you can't see in the pic. Individual hook up.
The relay shorts the Org wire (Full +12V) to the Purple wire (blower motor power wire) after the resistor pack, for full power. No problem with a common Batt.
Test yours by unpluging the 3 wire plug at the bottom of the relay. With the black lead of your DVM to a good gnd source, The green wire should go to +12V with the Key ON and the switch in the High position, only. If that's ok, check the Orange lead. It should be +12V all the time. If it's not, time for a repair.
The Org wire gets it's power from the + junction of power wires at the Horn relay stud, drivers side, midway up. the Org wire is fused near the power junction. The blower motor draws about 7 amps running on High. This is most likely the problem.
Note the rust
Time to replace it. Radio Shack can be very handy.
Cut it out, strip back about 3/16 of an in, each side, and crimp in Yellow butt splices.
Ready for the New fuse holder. Use a 20A fuse. You must use a fuse holder with 12 Gauge or greater wire attatched, 10 gauge prefered. the current runs about 12amps on high.
Here we are all crimped in with some heat shrink too. Crimp HARD. test by pulling slightly on the wires.
Heat shrink them or wrap them in two layers of good electrical tape.
Here we go. all neatly done,, and, the best part, the Blower motor works on High again!
Here is the resistor pack, pass. side air chamber. The fan uses one res. for off, a second one for low, both for medium and a bypass relay (next pic) for High.
The resistors reside in the air flow area. Good idea actually. GM is good for that.
Here is the blower relay. The green wire goes hot (+12V) on the switch selecting "High" & key "On". there is a seperate Blk Gnd wire towords the back of the relay you can't see in the pic. Individual hook up.
The relay shorts the Org wire (Full +12V) to the Purple wire (blower motor power wire) after the resistor pack, for full power. No problem with a common Batt.
Test yours by unpluging the 3 wire plug at the bottom of the relay. With the black lead of your DVM to a good gnd source, The green wire should go to +12V with the Key ON and the switch in the High position, only. If that's ok, check the Orange lead. It should be +12V all the time. If it's not, time for a repair.
The Org wire gets it's power from the + junction of power wires at the Horn relay stud, drivers side, midway up. the Org wire is fused near the power junction. The blower motor draws about 7 amps running on High. This is most likely the problem.
Note the rust
Time to replace it. Radio Shack can be very handy.
Cut it out, strip back about 3/16 of an in, each side, and crimp in Yellow butt splices.
Ready for the New fuse holder. Use a 20A fuse. You must use a fuse holder with 12 Gauge or greater wire attatched, 10 gauge prefered. the current runs about 12amps on high.
Here we are all crimped in with some heat shrink too. Crimp HARD. test by pulling slightly on the wires.
Heat shrink them or wrap them in two layers of good electrical tape.
Here we go. all neatly done,, and, the best part, the Blower motor works on High again!
