washer/ac/fan problems
#1
washer/ac/fan problems
hey so i have my 70 cutlass, and the fan ac, heater, fan vent and all doesnt work. niether does my window washer fluid sprayer, do these components link together somewhere. or have to do with each other
#2
No windshield washers is a common problem on GM of that vintage. The pumps just quit for no good reason, it seems like. You might luck up and find a replacement washer pump at a parts store, or I see rebuild kits on ebay all the time. It's not related to the heater fan issue.
On the fan- first check the fuse marked HEATER-A/C, top left of fuse block under the driver side of dash. If it's blown put the correct AGC-25 in. Also check for corrosion on the fuse clips. This fuse should be hot only with ignition in ON/RUN position.
Check for voltage at the blower itself. Not unheard of for one that old to die. Ignition in ON/RUN, probe for voltage at the plug while your helper runs the fan switch from lo to hi and back. If you don't have voltage at one or more positions, it's probably a burned out heater resistor (on the heater case underhood, passenger rear of engine compartment). If you have voltage and it don't run, either the blower motor has **** or you may have a bad ground connection.
If all that's good, you need to go inside the car under the dash. Look for a BROWN wire in the area of the HVAC control head behind the dash (hope you have good eyes and small hands). That's the main power feed. Check for voltage at the plug with ignition switch in ON/RUN.
There is also a black/orange stripe wire that goes from hi speed on the blower switch to the relay on the firewall underhood. If you only have no hi speed blower, the relay is the most common culprit.
Someone here may be able to post a 70 A-body wiring diagram, but if you're gonna keep the car and plan to do much of anything yourself, invest in your own 1970 Oldsmobile Chassis Service Manual. You will find it invaluable.
g
On the fan- first check the fuse marked HEATER-A/C, top left of fuse block under the driver side of dash. If it's blown put the correct AGC-25 in. Also check for corrosion on the fuse clips. This fuse should be hot only with ignition in ON/RUN position.
Check for voltage at the blower itself. Not unheard of for one that old to die. Ignition in ON/RUN, probe for voltage at the plug while your helper runs the fan switch from lo to hi and back. If you don't have voltage at one or more positions, it's probably a burned out heater resistor (on the heater case underhood, passenger rear of engine compartment). If you have voltage and it don't run, either the blower motor has **** or you may have a bad ground connection.
If all that's good, you need to go inside the car under the dash. Look for a BROWN wire in the area of the HVAC control head behind the dash (hope you have good eyes and small hands). That's the main power feed. Check for voltage at the plug with ignition switch in ON/RUN.
There is also a black/orange stripe wire that goes from hi speed on the blower switch to the relay on the firewall underhood. If you only have no hi speed blower, the relay is the most common culprit.
Someone here may be able to post a 70 A-body wiring diagram, but if you're gonna keep the car and plan to do much of anything yourself, invest in your own 1970 Oldsmobile Chassis Service Manual. You will find it invaluable.
g
#3
See if this helps...
https://classicoldsmobile.com/forums...-71-442-a.html
The washer is most likely unrelated. I have to give GM an F- on their washer designs. I have 3 GM vehicles and the washers are busted on all of them. My two olds need pump replacements. The Caddy needs a circuit board to fix its pump which costs almost 80 bucks! That ain't happening...
My old Ford uses a regular discreet electric pump which still works perfectly.
https://classicoldsmobile.com/forums...-71-442-a.html
The washer is most likely unrelated. I have to give GM an F- on their washer designs. I have 3 GM vehicles and the washers are busted on all of them. My two olds need pump replacements. The Caddy needs a circuit board to fix its pump which costs almost 80 bucks! That ain't happening...
My old Ford uses a regular discreet electric pump which still works perfectly.
Last edited by Lady72nRob71; May 10th, 2009 at 06:17 AM.
#5
Is it just the blower doesn't work, or does the control not do anything either? as in it won't switch from floor to dash vents to defrost? That usually indicates a vacuum problem.
Stick with us. We'll get you through it. You have a car more than twice as old as you are, and even though it's simple compared to new stuff, an HVAC system can be fairly complex.
Stick with us. We'll get you through it. You have a car more than twice as old as you are, and even though it's simple compared to new stuff, an HVAC system can be fairly complex.
#6
The fan/blower issue is likely a bad relay or it could just be the fan motor has bought the farm.
If your car has automatic temperature control it takes a different relay than a car with the standard manual temperature control.
If your car has automatic temperature control it takes a different relay than a car with the standard manual temperature control.
#8
Try this to determine if the blower motor is farked.
Look for a purple wire connected to the blower motor. Unplug it from the motor. Then run a jumper wire straight from the battery (+) terminal to the terminal on the blower motor. It should spin up to full speed.
If it doesn't, either a bad ground or bad motor. Bad ground= establish a good ground path. Bad motor= replace it.
If it does, it's the fuse, fan switch, resistor, or wiring.
Look for a purple wire connected to the blower motor. Unplug it from the motor. Then run a jumper wire straight from the battery (+) terminal to the terminal on the blower motor. It should spin up to full speed.
If it doesn't, either a bad ground or bad motor. Bad ground= establish a good ground path. Bad motor= replace it.
If it does, it's the fuse, fan switch, resistor, or wiring.
#9
Best troubleshooting methods have been mentioned above. Work slowly, step by step. If you need a more high res of the wiring diagram, PM me your email addy and i will send you the full version.
Do you have a voltmeter or test light?
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gregc
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September 12th, 2010 07:43 PM