Cold air blower
Discussion
Mine's blowing pretty slowly. Possibly blocked with leaves, possible faulty cold blower switch, possibly faulty output from heater control box 
I'll have a good go at it, when I'm on holiday from work, but as I can see the wires by the blower, I'm going to have a preliminary look tomorrow.
Motor appears to be a 2 wire type. Permanent 12v+ on the Green ignition wire.
And a switched 0v- on the Black/White wire.
So as I meter those Two wires, I'm expecting a varying voltage between 0 and 12 volts, depending on the fan control switch position.
I can also connect that Black/White wire straight to ground, and should get a full speed fan.
Anyone else had a play with either blower, and have I missed anything ?
I'll have a good go at it, when I'm on holiday from work, but as I can see the wires by the blower, I'm going to have a preliminary look tomorrow.
Motor appears to be a 2 wire type. Permanent 12v+ on the Green ignition wire.
And a switched 0v- on the Black/White wire.
So as I meter those Two wires, I'm expecting a varying voltage between 0 and 12 volts, depending on the fan control switch position.
I can also connect that Black/White wire straight to ground, and should get a full speed fan.
Anyone else had a play with either blower, and have I missed anything ?
I'd always assumed there was leaves stuck in my cold fan as it was so much worse than the hot fan. So when I rebuild the car I pulled the whole assembly out (was a right pain) but it was all amazing clean. So I just put the extra in line fan back into the pipe from the cold out let in to the central air box I'd fitted before. With both fans running it's just right. Search my user name & fans or something to find it if you want any info, hopefully the pics with my old threads will still work, they are still in the same host place.
I never checked the wiring to the org fan, would be interesting to see if you find any problem with that.
I never checked the wiring to the org fan, would be interesting to see if you find any problem with that.
Thanks, I've seen photos of the inline fan
My gut feeling is, it's going to be the switch or the controller.
Switch I presume, is going to have a varistor on it, to tell the controller what I want.
I'd then guess the controller takes that info and decides what voltage to send, to the blower.
I'll have a quick meter to see what's happening at that blower connection, but I think I'll end up connecting the blower direct to the battery, to see if it can blow at full power.
My gut feeling is, it's going to be the switch or the controller.
Switch I presume, is going to have a varistor on it, to tell the controller what I want.
I'd then guess the controller takes that info and decides what voltage to send, to the blower.
I'll have a quick meter to see what's happening at that blower connection, but I think I'll end up connecting the blower direct to the battery, to see if it can blow at full power.
Depending on your meter, You will see some odd voltages measuring across the two cables and may just see 12v regardless of position. This is actually quite normal, it's controlled by a microcontroller and is a Pulse Width signal. Not your traditional resistor shindig. Just connecting 12 across the motor is your best bet, if it runs perfectly, you have a controller issue.
Bit of an update, 2 minutes in.
Green ignition wire, is a permanent 12v+ as expected.
The other wire, as anticipated, varies the ground.
I turn the cold air knob on, and get 3 volts across the wires, twist it to maximum, and it varies all the way up to 9 volts.
Pretty certain that should be 12 volts.
I don't want to risk drawing too much current from that little ground next to it, for the RHS repeater, so I'm going to make a wire and pick up a good ground from the engine block, then see how the blower sounds and feels.
For further info, measuring across the blower is 5.3 ohms. Might be a handy figure to know, if ever you want to test for blower faults.
Green ignition wire, is a permanent 12v+ as expected.
The other wire, as anticipated, varies the ground.
I turn the cold air knob on, and get 3 volts across the wires, twist it to maximum, and it varies all the way up to 9 volts.
Pretty certain that should be 12 volts.
I don't want to risk drawing too much current from that little ground next to it, for the RHS repeater, so I'm going to make a wire and pick up a good ground from the engine block, then see how the blower sounds and feels.
For further info, measuring across the blower is 5.3 ohms. Might be a handy figure to know, if ever you want to test for blower faults.
RUSSELLM said:
Pretty certain that should be 12 volts.
Depending on your meter, it's actually probably correct. Unless you can get an oscilloscope on there to check the pulses, as you say, throw a ground at it and see how the fan is, but it does sound like your fan more than anything else.Jody
Slung the jump leads over to the footwell, and a short length of cable
Sort of good news... Blower sounds pretty powerful with 12v on it.
Bad news, next to find out whether it's the switch, module or a crap splice.
Worse news, is that even with that motor going full pelt, not a smidgen of air coming through.
Time to remove the ducting.
Sort of good news... Blower sounds pretty powerful with 12v on it.
Bad news, next to find out whether it's the switch, module or a crap splice.
Worse news, is that even with that motor going full pelt, not a smidgen of air coming through.
Time to remove the ducting.
Things looking up. Mass of air coming out of the blower, even at 9 volts.
That short piece of duct, then goes to the distribution box, behind the ashtray. I guess this duct could be blocked, so I'm going to try and get the end off, at the ashtray.
My gut feeling is, there's some kind of distribution flap, and it's stuck closed.
That short piece of duct, then goes to the distribution box, behind the ashtray. I guess this duct could be blocked, so I'm going to try and get the end off, at the ashtray.
My gut feeling is, there's some kind of distribution flap, and it's stuck closed.
Mystery solved.
There's a metal flap at the side of the distribution box, and it's siezed closed. Car was off the road for Three years.
Feels like I can force it open, if need be.
Before I do, does anyone know if that flap's electronically controlled, or is it just waiting for excess air flow, to open it up ?
There's a metal flap at the side of the distribution box, and it's siezed closed. Car was off the road for Three years.
Feels like I can force it open, if need be.
Before I do, does anyone know if that flap's electronically controlled, or is it just waiting for excess air flow, to open it up ?
RUSSELLM said:
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