4200 Blower Motor Issue - It's only the blower resistor that is failing!

rockits

rockits

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Evening all, as most of you know this has been my last issue to resolve on the 4200/GS hybrid. The blower was intermittently working. After a ton of troubleshooting of different things throwing me one way then another I thought best to get a decent Auto Electrician to look at it. That was fun to find one.....then one that was reliable!! Got there in the end.

I dropped the car down to Robert @ 3D Auto Electrical in Hatch End and as expected it seems like a small/silly/simple issue. Hold on….I'll rephrase the simple bit until further notice! It is the resistor on the blow motor that is the issue. I'm guessing it is causing the same as many resistors that fails with hot/cold cycles and surface rusting or breakdown of the surfaces they start to fail.

Totally explains the fact that the blower motor and the whole car/system works perfectly when it works. Also explains the AA75 error that comes up as a ‘blower' error when the error is displayed.

I am just trying to see if replacing the resistor is possible without removing the blower unit as that might mean dashboard out. The blower unit itself is working very well and he suggested there is no need to change this if the resistor can be source and replaced independently. If not it is a replacement blower. It is a real PITA as in many cars the resistor is replaceable independently, cheaply and easily accessible.

Anyone have any thoughts. ideas or experiences on replacing the resistor independently with blower in place? If blower needs to come out is it dashboard out for sure or is there a way with small hands and clever tools that it could be removed with dashboard left in place?

So close.....yet so far ;)
 
rockits

rockits

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Luckily it worked and failed while he was testing and all the electrics give all the right readings in both instances. Therefore all the right voltages are reaching the resistor when working or not. We can't prove this 100% without taking the blower out or getting to the other side of the resistor but he is 99.9% sure it is the resistor. It makes total logical sense to me from all the symptoms.

Bit of a pain for a likely £10 or £15 part. Depends if anything can be done without needing to take the whole dashboard out. I can't believe you have to take the dashboard out to change a resistor or the blower.
 
CatmanV2

CatmanV2

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zagatoes30 said:
Oh I can, no one would have designed it for this part to be replaced standalone never mind in situ
Click to expand...

This, sadly.

Not shown on the Eurospares diagram. Thinking a bit ore laterally, not 100% sure why there would be a resistor on the blower.

C
 
rockits

rockits

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Seems like on most resistors from what I can see there is a thermal fuse on one pin. For the cost of the blower it seems better to just replace the blower. If there is a way to get it out without taking the dash out I'll find it! Seems quite accessible upside down with your head in the foot-well. I wonder how many people have had their heads in the foot-well of Maser with their legs akimbo on the air?!
 
rockits

rockits

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Funny they say fix the fault in minutes from for £2.25.....yes £2.25 for the part and a zillions hours labour taking the dash out!! I could do it myself but running out of time and energy.
 
maverick

maverick

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A bit late to the party , but I had intermitent issues with my blower , found out to be the wires going into the housing had water damage and was corroded , believe it or not there are push on connector . It's a right pain but can be done but I pulled the connector off cut them and replaced with new spade connectors ,than with a mirror a touch a pair of long nose pliers , head in the foot well, legs each side of the seat and about a hour of cursing managed to push them back on , has worked fine since . Easy to tell if that may be the problem if you remove the rubber grommet and it wet in side ( I had water pour out ) than I bet the terminals are all corroded up .
 
maverick

maverick

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There is one which we are all familiar with ,the one that gets hot and one inside the housing behind the rubber grommet on the bottom
 
rockits

rockits

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maverick said:
A bit late to the party , but I had intermitent issues with my blower , found out to be the wires going into the housing had water damage and was corroded , believe it or not there are push on spade connectors . It's a right pain but can be done but I pulled the connectors off cut them and replaced with new ones , than with a mirror a touch a pair of long nose pliers , head in the foot well, legs each side of the seat and about a hour of cursing managed to push them back on , has worked fine since . Easy to tell if that may be the problem if you remove the rubber grommet and it wet in side ( I had water pour out ) than I bet the terminals are all corroded up .
Click to expand...

Thanks Mav.....very helpful & useful to know. I'll have a look.

Out of interest did yours work at all at any point? I have an intermittent issue. Doesn't seem to jump on or off with movement or bumps etc. as you might expect.

For example this morning before I left to take the car to the auto electrician I started the car....no blower. Left it running for 5 mins then switched off & locked up. Two hours later I left....car hadn't moved a millimetre. Open the car & turned on....blower working fine. Continued to work perfectly all way to auto electrician.

He turned it on a few hours later still working fine......then failed a few restarts later.
 
BL330

BL330

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Here's some photos of the blower removed

Blower Fan lower front view.jpg
Blower Fan underneath rear view.jpg
Blower fan air duct mounting points rear view.jpg

If you have to remove the blower fan unit, the attachment to the heater box is the air vent in last photo.
It cannot be separated from the blower fan as it is riveted in.
There is a tricky screw pictured at the top rear near the firewall about a third of the way down, that requires a small 90 degrees racket screwdriver and small hands to reach.
It is also a bast@rd to get back in.
If you have to go to this extent you may as well change the heater matrix.

All the best
 
BL330

BL330

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Here's some photos of the blower removed

View attachment 40297
View attachment 40298
View attachment 40299

If you have to remove the blower fan unit, the attachment to the heater box is the air vent in last photo.
It cannot be separated from the blower fan as it is riveted in.
There is a tricky screw pictured at the top rear near the firewall about a third of the way down, that requires a small 90 degrees racket screwdriver and small hands to reach.
It is also a bast@rd to get back in.
If you have to go to this extent you may as well change the heater matrix.

All the best
 
maverick

maverick

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1,982
rockits said:
Thanks Mav.....very helpful & useful to know. I'll have a look.

Out of interest did yours work at all at any point? I have an intermittent issue. Doesn't seem to jump on or off with movement or bumps etc. as you might expect.

For example this morning before I left to take the car to the auto electrician I started the car....no blower. Left it running for 5 mins then switched off & locked up. Two hours later I left....car hadn't moved a millimetre. Open the car & turned on....blower working fine. Continued to work perfectly all way to auto electrician.

He turned it on a few hours later still working fine......then failed a few restarts later.
Click to expand...

It worked on and off , but mostly off when it had been raining (go figure ) I use to just wiggle the wires and it would come on or I switched the car off and on again but after a while it just gave up so I had to try and find the problem lucky for me it didn't evolve tacking the dash out .
 
rockits

rockits

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Thank BL330. I thought the smaller blower unit came off separately so that is why I thought it could come out without the dash coming out. If you have to take all that attached stuff out I can see why the dash needs to come out!

Did you need to take the dash out? Is there no way to get the blower off and out just as the blower only? Are there not some screws there?
 
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