Front heater blower

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Lemner
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Front heater blower

Post by Lemner » Mon Jun 27, 2022 10:25 pm

Hello All,
I have a 96 2.5 diesel with the manual slider and rotary speed control type heater controls.
I have just discovered that the fan speed controller switch isn't working. To be honest I haven't tried this for a few months as my van has been off the road due to a head gasket issue. I've recently fitted a Davies Craig electronic water pump system to try to overcome the cooling problems that I have had in the past, see my earlier post- with a lot of help from Geoff. This is all working great so far.
I can only assume that I may have inadvertently caused this issue, but I don't know how. Oddly enough, the rear heater fan stopped working a while ago.

By process of elimination, I have found that I have a type 2 fuse box by the drivers side door. For the permanent 12v feed to the EWP controller I re-purposed fuse 14 that would normally run electric blinds- I don't have these. The switched 12v came from fuse 5- Air con. This wire had been cut by a previous owner. Apart from connecting the EWP to the radiator fan relays, I haven't changed anything else.
Another thing that recently took place was the removal of the air con pump as this has never worked since I bought it.

The fuse in the under-bonnet box is fine and there wasn't any corrosion sometimes caused by water dripping onto it. I've located the connector to the fan (I hope) judging by the wires that connect on then run round to the right side before going into the fan housing. These isn't a voltage reading there with the ignition on and the fan switch on.

I have read a few posts on the forum, would anyone be kind enough to let me know where I can find the relay and the resistor pack.
I believe this may be a possible cause?

Any other advice and guidance would be greatly appreciated.
Many thanks, Ian.
Clever people the Japanese.
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g8dhe
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Re: Front heater blower

Post by g8dhe » Tue Jun 28, 2022 9:16 am

The resistor pack (with its thermal fuses which are often the problem here) is located where the probes are below;
probes.JPG
The resistor pack is here and the tabs are soldered down, when they get hot the solder melts and the tab flips up, minimal solder is needed and I suggest if they have popped use as much of the original you can as I don't know if its a low melting point solder or not!
heater_fuses_2.jpg
Geoff
2001 Aero V6, AFT, full side conversion.
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Lemner
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Re: Front heater blower

Post by Lemner » Tue Jun 28, 2022 9:45 am

Many thanks for your help again Geoff, i'll take a look tonight.
Clever people the Japanese.
Lemner
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Posts: 26
Joined: Wed Jun 15, 2022 8:35 am

Re: Front heater blower

Post by Lemner » Tue Jun 28, 2022 5:44 pm

Hello Geoff,
I've had a look at the resistor pack and all looks OK. The solder has not melted.
Sorry to ask, but can you think of anything else but can you think of another cause please?

Many thanks
Ian
Clever people the Japanese.
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g8dhe
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Re: Front heater blower

Post by g8dhe » Tue Jun 28, 2022 7:31 pm

Unplug the motor (2-pole connector on lead from fan unit) and apply power, that will confirm if its the fan that is faulty or not.
After that check the fuses and the relay;
Air_con_manual_1.JPG
Geoff
2001 Aero V6, AFT, full side conversion.
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Lemner
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Re: Front heater blower

Post by Lemner » Tue Jun 28, 2022 8:10 pm

Hello Geoff,
Thanks again for your reply. The fuse at the under bonnet fuse box and that is OK. Power isn't getting to the connector nearest to the fan.
Do you know where the relay is located please?

Best regards
Ian
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g8dhe
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Re: Front heater blower

Post by g8dhe » Tue Jun 28, 2022 11:32 pm

Yes its on the offside wing, 3rd from the front, last of the block of three G1-03.
Geoff
2001 Aero V6, AFT, full side conversion.
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Lemner
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Re: Front heater blower

Post by Lemner » Thu Jun 30, 2022 10:08 pm

Many thanks Geoff.
Taking a look at the wiring diagram has highlighted the issue.
Fuse 5 is marked as air con but also has a common connection with the front heater fan relay.
I had assumed that it only did the air con (which hasn't worked in years) so cut the wire at the back of the fuse box and re-purposed the fuse for the switched 12v to the EWP.
I had also misremembered that the wire from fuse 5 had been cut by a previous owner which didn't help. Should have taken another look- it was the wire from fuse 20.

I should have just re-traced my steps backwards from the start!

Much respect
Ian
Clever people the Japanese.
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