One for the auto electricians out there

I added this question to the end of a previous, associated, post but its slipped to oblivion and of course I didnt get any answers. So try again.
When I replaced the fuse for my heater blower, it sparked and fused again. ?live wire.
How do I proceed from here? Unfortunately, I know nothing about electrics

chances are the motor is seized. Remove it and check.

Ask JP - he is the fan motor expert .

Have you checked:

the motor turns

the switch (lever) is wired properly

the earth is actually earthed

This is a right pain in the arse!!! good luck

chico929 said:

I added this question to the end of a previous, associated, post but its slipped to oblivion and of course I didnt get any answers. So try again.
When I replaced the fuse for my heater blower, it sparked and fused again. ?live wire.
How do I proceed from here? Unfortunately, I know nothing about electrics

Click to expand...

First question. When you put the new fuse in and it blew immediately, was the fan switched to the on position as you did this?
Second, is the fuse the correct rating for the circuit?
Third, try a new fuse with everything switched off first.

If it still blows, consider reading on.

If you can get your fingers to the fan, try to move it by hand, it might just be stuck, then try new fuse again.

OR

And this is not highly recommended unless you are confident enough to know the difference between the spark from a serious short circuit and the spark from a heavy load of a live circuit's spark, but if you were to put a live feed from the battery (or some other 12v source) to the motor connections, BUT JUST TOUCH THE WIRES TOGETHER FOR A SPLIT SECOND this might give the motor a kick to get it turning. If it doesn't spark a huge spark (like accidentally shorting your jump leads) then try a slightly longer contact and see if the motor turns normally.

If this gets things turning ok and a new fuse blows again, check all the wiring for a short circuit from the motor back to the switch. It's most likely to be chaffed wiring somewhere shorting to the vehicle body. Off the top of my head, I don't know if this fuse serves more than one circuit, if so, it might even be something else that is causing the problem.

Cheers M.H.M.....I`ll pm JP if I get no joy with `simple` stuff!!
bluehaze and Clanforbes....I`ll check the basic stuff u suggest ta.
Clanforbes......the OR section is a bit too complex for an electrical virgin, as u said. I`d prob burn the loom out or something daft , but I will go thru the process of elimination u both suggested. Thanx again.

unplug the motor and put the fuse in, if it doesn't blow it's the motor. or unplug the motor and use a multimeter to check the resistance at the plug, if it just shows 1 it's dead.
if it still blows a fuse with the motor off it's a loom fault or a switch fault.

Thanx gegs.
I`ve written all these suggestions down and will work thru them. Thanx everybody.

Hi, got your message...

basically, what was said above.

if the fuse only blows when the fan motor is switched on, disconnect it from behind the heater box and put a new fuse in and turn the switch on, if it doesnt blow, its the motor

let us know your findings

Thanx for getting back to me JP.
I`ll post up whatever I find and have to do, to fix it.

Right, first things first.
Undid the wing scoop and, hand down the pipe to the fan revealed at least a fistful of solid soil up against the fan and in the blades.
After excavation, the fan was still locked solid.
More digging and poking to loosen the soil, allowed the fan to eventually start to turn, but still very very stiff.
The plan on Friday is to remove everything to gain access to fan, motor and matrix, clean everything and lube. If all goes well...great.
But I`m thinking while I`m in there, should I have a new/used motor ready to fit if the motor is actually sha**ed?
Are they quite hardy or fragile?
Has anyone, perchance got a decent 2nd hand one to sell on, just in case.
I didnt do one of the tests cos I couldnt find an on off switch to the motor!

the motor doesnt have an on off switch!

but if you get your hand behind the motor, there's wires there, pull it out and disconnect the wiring there, actually, I think the connector sits on top of the heater box against the bulkhead.

unplug that and test it, like explained before, by operating the lever inside, if the fuse doesnt blow, its your heater motor.

but seeing as you have already found soil and the motor is stiff....your motor might be shot

Ah, thanx (JP), nice to have confirmation.

Update.......
First my thanx to JP, Clanforbes and gegs88 for the advice.
We did strip the heater box out, (what a fiddly f**k that was), the fan motor was indeed dead. Only tore a little of the foam seal as well which glued back in place well enough! Got 2nd hand motor from breakers, which was fitted today. With a new fuse in place, the first test ......success.
Now have warm toasty cab. Those other peeps who ask whats the fuss about Landy heaters, there not lying, they do work when all components are in good order.
Shame the snow/cold is all gone
Cheers again all who pitched in.