Blower and switch wiring detail Mk1a?

Cdntiger

Gold forum user
Messages
120
Hi,
I am replacing the entire wiring harness in my Mk1a with a factory type replacement from Rick.
Buba had previously jury rigged something to run the blower motor, does anyone have the correct wiring diagram with correct colors for the switch and blower motor?
I have two wiring diagrams for the car, but neither has detail on the switch and blower motor.

Many thanks,

Paul
 

66TigerMK1A

Gold forum user
Messages
1,129
Can't help with the colours much but the heater motor has a black ground wire to a bolt and 2 wires running to the switch, one from the resistor for low speed and another for high... the switch ( and radio if fitted ) is fed power from #4 terminal on the ign. switch. I will post the most common pinouts for the Lucas toggle switches in my albums. http://catmbr.org/VB_forum/album.php?albumid=69

You can confirm with an ohm meter...

Edit: I had a look at some spare switches and have one labeled 342810? and has a blower tag on it ... it has the same pinout as the 31788 in my gallery which has connectors at 1,4,6,7 & 8
 

norm1

Gold forum user
CAT Member
Messages
283
Single Speed blower

My diagram shows a green wire from ignition switch #4 to switch and black wire to motor. looks like motor itself is grounded.

MkII is 2 speed.
 

66TigerMK1A

Gold forum user
Messages
1,129
My diagram shows a green wire from ignition switch #4 to switch and black wire to motor. looks like motor itself is grounded.

MkII is 2 speed.

MK1A and MKII are both 2 speed... looking through my wiring diagrams they show them fed from different sources,though. MKII through the 'switched' fuse via a terminal on the water temp gauge but MK1A from acc (#4 ) on ign. switch. It seems that every wire that comes off that switched fuse is green!:confused:
Not so sure what colour would come off the ign switch but it might be green too :eek:
 

PITT40

Gold forum user
Messages
531
This was sent to me from another member when I was having blower issues. Hope it helps. Sorry misspelled blower switch when I scanned it.
 
Last edited by a moderator:

Cdntiger

Gold forum user
Messages
120
Thanks for all the great info guys!
Here is what I have;

The resistor has a green wire on one end, a brown wire on the other, they plug somewhere on the blower switch.

The blower motor itself has one wire grounded to a bolt, the other wire was badly spliced to a red wire that plugged somewhere on the blower switch.
I will remove the red and do a proper splice with the correct colored wire.

The new harness kit came with a green wire that I figure must go from the #4 position on the ignition switch to somewhere on the blower switch, I will check the diagrams again that you guys sent.

Cheers,

Paul

View attachment 7369

View attachment 7370

EDIT: Just looked at your drawing PITT40; since the blower can operate at two speeds, I would think that there should also be a wire direct to the blower motor? In other words, for low speed the power is sent from the switch through the resistor and then back to the switch, then back to the motor. For high speed, directly from the switch to the motor?
 

PITT40

Gold forum user
Messages
531
No wire direct to blower. Power goes to the switch and goes to one wire for high and the other wire for low speed. Trust me it works.
 

Cdntiger

Gold forum user
Messages
120
No wire direct to blower. Power goes to the switch and goes to one wire for high and the other wire for low speed. Trust me it works.

Thanks, but the blower motor wire has to be connected to something?
The first of the two motor wires goes to the ground bolt, what about the second one?

Thanks,

Paul
 

66TigerMK1A

Gold forum user
Messages
1,129
No wire direct to blower. Power goes to the switch and goes to one wire for high and the other wire for low speed. Trust me it works.

Sounds right!!
I went out and dug up my spare to have a look...

Power will go from ign. to the switch first...
when you toggle it to 'low speed' position, 12 v. will go the motor via the 'green' wire only... the resistor will drop the voltage to say 9 v. ? maybe and the motor will run slow... when you toggle the switch to the 'high speed' position, 12 v. will go to the motor via the 'brown wire' bypassing the resistor and supply 12 v. directly to the motor giving it full speed !

Think of it a bit like the ign. system to the coil. When the key is 'on', the 12v. from the ign. goes to through the ballast resistor and drops the voltage to the coil but when you turn the key to 'start' , it sends 12 v. down a different wire to the other side of the resistor giving the coil a full 12 v.
 

Cdntiger

Gold forum user
Messages
120
Thanks Jim, your picture clarified it for me, the positive lead on the motor goes to the resistor, and not to the switch as Buba had wired mine.
I'll test the resistor to be sure it's still good.

Paul
 
Top