Datsun 210 heater not working

[wobbedennis]

Ok, I know it has been a long time since I have been on, but I haven't needed any help in a long time. It's has been great, even went on a road trip with no hiccups, except my long legs cramping up. But the weather here in the Truckee Meadows has turned cold. We got two inches of snow last night, and I want my heater in my car to work. I went through last winter without it, and I'm not going through it again without it. I started work on it, and here's what I have found.

The fuse is good, the radio works, and they are on the same circuit as far as the fuse is concerned. I don't know if it's the switch, but I need a multi-meter to test, a tool the failed on me over the summer. (I knew it was coming, it was a cheap harbor freight one) so I can't test there, but I don't know how the heater is wired. it's just odd. I have no power going to the blower motor though, and when I try to hot wire it, to see it's operational, and I almost caught the car on fire, it burned the wire. BUT I don't know it that was the ground I hooked it to, and that caused it, I tried to work it through the switch. HELP

[datzenmike]

Power from the fuse goes directly to the motor and it's how it's grounded that turns it on and regulates the speeds. So the ON switch merely grounds the wire from the motor.  Grounding the motor through a coil or resistance makes it run slower for speeds.

[wobbedennis]

ok, I haven't tested the other lead wires yet to see if it has power.

[wobbedennis]

Also, When it worked last year, I only had the high speed on the motor, or off, and it's a three speed, or it meant to be.

[wobbedennis]

ok, good news, I have power to the motor, and on one wire to the switch, but no other wires are getting current to the switch, I see a plug at the top of the heater box that all of the wires from the switch run into, what does that do, and could that be my problem?

[datzenmike]

Just remember the motor already has the power to it. The wire from the motor only needs to be grounded to make it work. This is what the on off switch does, it just grounds the motor to turn it on.

 

Here is a resistor coil from a 620. Instead of going directly to ground which gives HI speed, power is run thorugh this and the motor runs at a slower speed.

[wobbedennis]

where is the resistor coil at on a 210?

[wobbedennis]

Ok I played with it some more. When I hot wire the hot side of the switch to others, I get the blower motor to turn on in other areas. The switch is fine, but the resistor coil is shot. where is it and How do I replace it if it's replaceable

[wobbedennis]

NVM, Found it. It vibrated apart, and disintegrated when I tried to put it back together. I'm just going to slap it back in and hunt for a good one. In the mean time, I'm going to rig something together so I can have a heater. If you guys find one laying around or something, or you think of me and look and find one, let me know. I'll be watching this topic close to see if I find one. I'll also post in the wanted ads. 

[wobbedennis]

I was able to get the original working. I soldered it back together.

[datzenmike]

It gets hot so solder may not hold. It is also mounted inside the sir stream to cool it. Glad you got it.