Heater blower relay

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balto8
Knows an Aerodeck isn't a 480
Posts: 221
Joined: Tue Jul 22, 2014 3:02 pm

Heater blower relay

Post by balto8 » Sun Dec 20, 2015 12:26 pm

Where is the heater blower relay (E9)? I have located B2 and B12 behind the glovebox and a couple of fuses there too, but I can't find E7, E8 and E9.
1991 480 Black Turbo
2012 Seat Exeo ST
2013 VW Polo TSI DSG

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brinkie
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Re: Heater blower relay

Post by brinkie » Sun Dec 20, 2015 4:44 pm

What do you mean with E7, E8 and E9? The heater blower relay (for cars without VEM) is numbered 3.25 in the schematic diagrams I have. You should find it, if you follow the white-red and white cable from the blower switch. I have never worked on right hand drive 480's and the schematics show a left hand drive car, my best guess is that it's located next to the blower.
Robert.

Present cars: 1994 Volvo 480 GT 2.0i Vase Green, 2010 Volvo V70 2.0F Momentum Mystic Silver
Past: 1981 Talbot-Matra Murena 2.2 Rouge Mephisto, 1995 Volvo 480 GT 2.0i Paris Blue

balto8
Knows an Aerodeck isn't a 480
Posts: 221
Joined: Tue Jul 22, 2014 3:02 pm

Re: Heater blower relay

Post by balto8 » Sun Dec 20, 2015 5:10 pm

It's a LHD 1991 b18ft,with old type VEM, with off and rec at the right side and acmax and ac buttons on the left. On the back of the fan all there are two relays with their fuses. Those two are fuel pump and injection. I'm starting to think I don't have a heating fan relay.
1991 480 Black Turbo
2012 Seat Exeo ST
2013 VW Polo TSI DSG

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brinkie
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Posts: 605
Joined: Mon Apr 21, 2014 11:20 am
Location: The Netherlands
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Re: Heater blower relay

Post by brinkie » Sun Dec 20, 2015 6:24 pm

If your car is equipped with a VEM, the relay is located inside the unit. It is a common fault that either the highest speed or the blower altogether stops working. You have to take the VEM out, open it up and re-solder the points that connect the relays to the PCB.

It is quite an annoying job to take the VEM out of the dash, should be described somewhere on this forum. Opening it up is simpler, just unscrew it and remember where the screws came from. Pry out the light bulb sockets and take the unit apart. Don't forget to put new light bulbs in. They are very cheap and it will take the same annoying effort to replace them, if they blow after the unit is back in the dash. Take care not to lose the small rubber rings inside the vacuum connectors otherwise you will have an air leak and of course test everything before putting the dash back together :wink:
Last edited by brinkie on Sun Dec 20, 2015 9:24 pm, edited 1 time in total.
Robert.

Present cars: 1994 Volvo 480 GT 2.0i Vase Green, 2010 Volvo V70 2.0F Momentum Mystic Silver
Past: 1981 Talbot-Matra Murena 2.2 Rouge Mephisto, 1995 Volvo 480 GT 2.0i Paris Blue

balto8
Knows an Aerodeck isn't a 480
Posts: 221
Joined: Tue Jul 22, 2014 3:02 pm

Re: Heater blower relay

Post by balto8 » Sun Dec 20, 2015 6:37 pm

That's great help.

I had the only ACMax working situation in the past. I did open the VEM and resoldered points as said somewhere in the FAQ. It worked for a while. Now the whole unit has gone. I get the lights on the buttons and the VEM slider but no air at all comes out, regardless of the fan speed selector position.

So a VEM will be.

Anyone with a spare working VEM for my model?

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1991 480 Black Turbo
2012 Seat Exeo ST
2013 VW Polo TSI DSG

User avatar
brinkie
480 Expert
Posts: 605
Joined: Mon Apr 21, 2014 11:20 am
Location: The Netherlands
Contact:

Re: Heater blower relay

Post by brinkie » Mon Dec 21, 2015 9:12 am

There's almost nothing that can go wrong with these units, save for bad soldering joints. But you really have to solder carefully, using a clean soldering iron (not too powerful, 15 to 30W) and 60/40 rosin core solder.
Robert.

Present cars: 1994 Volvo 480 GT 2.0i Vase Green, 2010 Volvo V70 2.0F Momentum Mystic Silver
Past: 1981 Talbot-Matra Murena 2.2 Rouge Mephisto, 1995 Volvo 480 GT 2.0i Paris Blue

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