W124 heater motor fuse?

[coneybiller]

Hi all, I’ve searched the net profusely to find out what’s going on with my heater blower motor, but it doesn’t seem to be of much help! So I turn to the wealth of knowledge from your kind selves!

I have a 96 E320 W124 estate, which I picked up on Saturday and now the blower motors given up! It was working fine on the return journey when I collected the car, but not worked since then. No speeds whatsoever. Including flat out.

The car does have A/C but not climate control.

I’m led to believe that there should be a flat strip-type fuse located outside of the fuse box, somewhere near a wheel arch, but it doesn’t seem to exist. I’ve found what appears to be the resistor, which is like a cage with some coils of wire, up behind the brake booster, but still no fuse!

I’m thinking I’m going to have to go and buy a multi meter. Any ideas on where to test for a feed?

Regards

Ben

 

[coneybiller]

Anyone?

 

[optimusprime]

This is it .

 

[coneybiller]

Where abouts am I supposed to be looking?
I believe the fuse connected to the battery pos and negative(why it has a fused neg I’m not sure??) is for the after market radio, but I’m not entirely sure. Both fuses are good either way.

 

[optimusprime]

You are in the right area . Just open every box you can see it must be in there looking at the picure above mine is next to the oblong box i can see .

 

[optimusprime]

Ben the fuse your after was fitted in the fuse box fuse no-12 .No auto climate control then the fuse is in the main fuse box.

 

[coneybiller]

Fuse 12. OK I’ll check that later. Brilliant thanks a lot for the help, most appreciated! Fingers crossed it’s a duff fuse

 

[coneybiller]

Well I haven’t got a multi meter so couldn’t check fuses, however, it appears to be a 25A fuse that’s in situ. I swapped the blower motor (12, how I missed that so don’t know!) with the rear window motor fuse. The rear windows still operated but the fan still does didly squat! No power on any settings including full speed.
It’s looking like a duff blower motor. I suppose I’m going to have to take it to bits and see if there is power to the motor.
Is there an easy connection to get to to check input power to the motor, without having to take the wipers/panels apart?

 

[optimusprime]

If you still have the old type fuses that are white metal .I would change them asap for copper and cramic . But change them one at a time to make sure you replace only the ones in use . Take a picture before you start .

 

[Ted]

The fan on my w124 would intermittently stop working.
A good slap on the passenger side at the front of the centre console would get it going for a time.
This pointed to the brushes on the heater motor being worn.
Could save you a bit of diagnostics.

 

[WDB124066]

Don't forget to take a look at the switch on the dash too, I've had bits of metal rain out of mine, so they do fail. Control board behind the switch may have the famous dry solder joint which sometimes can be remelted successfully with a fine tipped iron and a steady, quick hand.

 

[coneybiller]

If you still have the old type fuses that are white metal .I would change them asap for copper and cramic . But change them one at a time to make sure you replace only the ones in use . Take a picture before you start .

Ahh yes I’ve heard about these fuses not standing the test of time. Where’s the best place to get them from? Mercedes?

The fan on my w124 would intermittently stop working.
A good slap on the passenger side at the front of the centre console would get it going for a time.
This pointed to the brushes on the heater motor being worn.
Could save you a bit of diagnostics.

Was yours an A/C equipped car? As I’ve heard there’s a few different varieties of motor (twin fan and single).
It will be back on the road later today after replacing a split CV boot that had sprayed its grease everywhere. I’ll give that a try!

Don't forget to take a look at the switch on the dash too, I've had bits of metal rain out of mine, so they do fail. Control board behind the switch may have the famous dry solder joint which sometimes can be remelted successfully with a fine tipped iron and a steady, quick hand.

Haven’t read about this issue. Is it a case of taking the heater/blower control panel to pieces? Some form of PCB with solder tracks?

Regards

Ben

 

[Deadly Dave]

I got my copper fuses on eBay.

15 x 8 + 16 + 25 Amp Bullet Torpedo Fuses Copper Brass Mercedes W123 W124 W126 | eBay

 

[Ted]

@coneybiller, not ac - just the standard heating - good luck, hope it gets sorted

 

[optimusprime]

Try you local boat yard chandlers they will have them .

 

[WDB124066]

Pull the dash out by the switch and all will be revealed, there is an instruction from MB on how to do this. A replacement switch is cheap enough from a breaker to see if that does it or a swap out of the PCB may show you the board may respond to a re-solder.