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Heater

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Jeepster

Jeepster

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This may sound like a stupid question but how should my heater be set to get warm air out of it? Time has come for me to address the heater and see if I can get it working. At the moment I dont get cold or warm air flowing through it!

The slider obviously gives warm or cold air with warm when its pushed to the right hand side.

How do you get the fan to run? Before I can see if the fan has failed I need to know how you would switch this on ?

Whats the function of the push/pull knobs?
 
Jeepster said:
How do you get the fan to run? Before I can see if the fan has failed I need to know how you would switch this on ?
Click to expand...
The slider has a switch in it (heater booster). Pull to turn the fan on. Here is a photo of the back.
 
Jeepster said:
...

Whats the function of the push/pull knobs?
Click to expand...

I have a BJ8 but I believe the earlier cars function the same: the knob on the left opens and closes--pulled out is open--the driver-side fresh air vent. The knob on the right controls air passing through the heater core; pulled out is shut. So, both knobs in and slider to the right is full heat, both knobs out and slider to the left is max cool (for the driver). If you close the slider (to the left) and push in the right-hand knob you can get some fresh air to the passenger footwell (after the heater core cools down).

All air from the heater is ducted through a box-section channel on the scuttle (firewall) and a couple hoses to the defroster vents. There are flapper valves on either side of the channel that must be open to get air from the heater to the footwells.

Defrost is on if the heater is on--there is no switch or valve.
 
Now it makes sense. The switch is inbuilt with the slider.

I can now check to see why the blower does not function.
 
The most consistantly reliable British car heater that I've ever used:

:iagree:


Keoke----------------------------------- :laugh:
 
Bob_Spidell said:
Jeepster said:
All air from the heater is ducted through a box-section channel on the scuttle (firewall) and a couple hoses to the defroster vents. There are flapper valves on either side of the channel that must be open to get air from the heater to the footwells.
Defrost is on if the heater is on--there is no switch or valve.
Click to expand...

To get a little more air pressure to the demisters, close both flapper valves on the box channel. As Bob mentioned, they are on the bottom of the box-section, left and right sides. The flappers are spring loaded. Simply give them a push and they'll snap closed. Pull them to open.
Click to expand...
 
Looks like the problem is with the slider switch. I checked for 12 volts on the input wiring to the fan with the slider fully to the right and nothing.
Whats the easiest way to get access to the switch? I could do without taking the left and right dash panels off.
 
Jeepster said:
Looks like the problem is with the slider switch. I checked for 12 volts on the input wiring to the fan with the slider fully to the right and nothing.
Whats the easiest way to get access to the switch? I could do without taking the left and right dash panels off.
Click to expand...

Just want to make sure you understand the operation of the switch. Whether it is moved to the right or left does not control the operation of the fan. In addition to moving right or left, the button marked "Heater Boost" also slides in and out. This is what turns the fan on and off. Sometimes they can stick if they haven't been used in a while and need a bit of persuasion. You might want to check if your blower motor works by connecting a 12 v hot lead directly to the green/brown wire leading to the motor. However, the blower motor can sometimes fail to start as well with disuse and nudging the "squirrel cage" will help getting it going again. (You'll have to remove the air hose to the blower to get to it) If you have a BJ7 and you need to remove the switch, there are a couple of bolts you can access from beneath the dash. Be careful when you remove them and watch the placement of the metal spacers so you can properly reassemble. If the switch isn't working, I'd probably try some contact cleaner before purchasing a replacement.
 
Rick,

thanks for the update as I did not know that the switch also moved forward and back. I was under the impression that it switched on the fan just by moving it to the right. I will give that a try and see what happens.
I see what you are suggesting about the 2 bolts with the spacers. Maybe I am less flexible that the rest of you but that looks like it would be a nightmare to remove and then replace without removing any of the dash frontage.
 
Rick,

I just had to check if pulling out the slider would get the blower moving so just popped to the garage . . . . . . . .


and . . . . . . .

still doesn't work.
 
Jeepster said:
Rick,

I did check for voltage at the blower motor and nothing. Its a BJ8.

I'm convinced its the switch.
Click to expand...
If you don't have a meter to verify the output of the switch, then you can't be sure...

Pull the wires from the switch out of the harness connections, and put the two harness wires (that were connected to the switch) together. This would bypass the switch and send 12V to the blower...
 
Rick, nice job covering all the bases.

I'll add one comment about the R&R of the heater control panel. It's made out of bakelite I think. Pronounced....wait for it.... break-like, as it will break if twisted or too much pressure is put upon it.

If you do take it out, give it good cleaning. Most likely the grease had hardened over the years and the wire contacts may not be making good contact. The two wires may also be frayed from the movement of the slider over the years. Lots of things to look at while you have it out. You don't need to remove the wood, but removing the center consul will help in trying to get your hands up there to get to the nuts. Ah, good times ahead on that one.

Have you tried spraying any electrical cleaner down the lever control? It may just be gummed up. Grab the heater boost knob, pull and push it a few times while spraying. You may get lucky.

Cheers,
Roger
 
Update -

The blower is fine as I connected 12 volts directly to it.

The switch is fine, I managed to get my multimeter up to test the contacts.

Turns out the fault lies with the wire that connects the switch to the blower. Its open circuit somewhere along the line? The harness is not in the best condition so it might be easier to run a new wire between the two points?
 
Couple of other things to check: take apart the bullet connect leading to the blower and clean the connections with some emery cloth. Also check the fuses in the fuse panel to ensure you don't have a blown fuse and clean the fuse panel contacts as well. Also, on my BJ7 at least, the power line to the switch runs first to the fuel gauge. You might want to take a peek at the connection on the fuel gauge to see if the power is going to the blower switch.
 
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