Heater Motor Not Working, Can't Find Resistor.

[OutbackAndBeyondUK]

Hi, I have a 2001 3.0 H6 with 'Climate Control/AC'. The heater does not blow on any setting. There is a beep when AC is selected and you can hear it engage, you can also hear the flaps moving in the dash to change the air direction when different modes are selected.
Online searches indicate a bad heater resistor, though my car does not seem to have one in the same place as indicated in diagrams and photos. I have studied various pics so know where the resistor should be and what it looks like.
Can you tell me whether the resistor can be an integral part of the actual motor fan and not a seperate item ?
Is the resistor only visable on cars without Climate Control ?
Any help will be much appreciated as I've just bought this car (first Subaru) and its starting to get cold !!!!!

[plain OM]

If your climate control is what we identify as "automatic" then it doesn't have a fan motor resistor.

The automatic control is just that -- set the preferred temperature and it will adjust the heat/AC temperature and fan speed to maintain it. In contrast, the manual system requires the operator to adjust the controls to achieve a comfortable level -- any change in the cabin has to be compensated by a manual change to the control settings, whether fan speed, temperature, or mode.

In the automatic version, in place of the resistor there's a power transistor that is used to control the current through the fan motor. This allows the system to vary the current, and thereby fan speed, electronically. The transistor is in the same location as the resistor would be -- in the duct, inboard of the fan.

If the fan motor doesn't run, the first thing to check is the power to it. There's a two pin connector at the fan motor. With it disconnected, with the ignition switch at ON, and the climate control set to have the fan running, there should be 12V at one of the two pins of the connector. This comes from the "blower motor relay", and upstream from there from two fuses, #1 and #2, in the in-cabin fuse box. (The 12 V will go off if the climate control is turned off, or the ignition key is switched to OFF.)

It's possible that the transistor has failed, or the control system is malfunctioning, but if you haven't verified the 12 V power to the fan motor, start there.

[cardoc]

Maybe this will help.

[plain OM]

Attached is a photo (typical) of the manual control heater resistor removed from the duct. (The resistor element itself is inside the perforated cover.) With the automatic controls, the power transistor would mounted in the exact same location. The photo (and the diagrams cardoc provided) are for left-side driver vehicles -- they would be reversed for your U.K. model, with the fan motor and duct under the front passenger (left) side dashboard.

Also, some of my diagrams show the opening for the resistor/transistor to be on the bottom of the duct as in the second attachment, instead of on the side as in the first photo. (Again, the diagram is reversed.)

Finally, the third attachment below shows what the power transistor unit might look like.

Let us know what you find.

[OutbackAndBeyondUK]

Thanks for the info. Will keep you informed on how it goes.

[OutbackAndBeyondUK]

So, I had power going to the motor so suspected a bad motor/transistor.
Luckily I came across a used Legacy motor on Ebay for £10 inc shipping so took the risk and bought it.
I have now fitted the motor which comes with the transistor built into the bottom of it where the power plug connects.
Should have been an easy job but as usual, the most inaccessable screw (out of only 3 !) was a pain to loosen without rounding of the head due to its location and the fact I couldn't see it without standing on my head !
Thanks for your input.

[OutbackAndBeyondUK]

Originally Posted by plain OM

Attached is a photo (typical) of the manual control heater resistor removed from the duct. (The resistor element itself is inside the perforated cover.) With the automatic controls, the power transistor would mounted in the exact same location. The photo (and the diagrams cardoc provided) are for left-side driver vehicles -- they would be reversed for your U.K. model, with the fan motor and duct under the front passenger (left) side dashboard.

Also, some of my diagrams show the opening for the resistor/transistor to be on the bottom of the duct as in the second attachment, instead of on the side as in the first photo. (Again, the diagram is reversed.)

Finally, the third attachment below shows what the power transistor unit might look like.

Let us know what you find.

When replacing my motor I did not see any resistors/transistor units or openings. The transistor on my car is screwed on to the motor (see pics on above post).
All cars with 'Manual Heaters/Blowers' must have seperate resistors screwed to the ducting and powered by a block connector (clearly seen on your pics) and cars with 'Auto Climate Control' have a transistor built onto the bottom of the motor (seen on my pic).
Thanks for taking the time to post your pics.

[plain OM]

Interesting.

On opposed forces, the relevant European RHD page (http://opposedforces.com/parts/legac...llustration_4/) shows a separate power transistor unit (#31), which appears to be mounted on a sloped portion of the intake duct, inboard of the fan.

The North American equivalent model page http://opposedforces.com/parts/legac...llustration_4/) shows two devices, #32 -- resistor assy, or #33, not identified other than for "auto" but presumably the power transistor for the automatic climate control. Either fits into the duct.

Perhaps the European page isn't correct, or there was a design change along the way.

Something else learned.

In any event, happy that you resolved the problem and have the fan going again, especially as the weather begins to cool.

[OutbackAndBeyondUK]

I've just ordered a cabin filter, so when I fit that next week I'll take a pic of the heater motor and area around it as it may help others who have the same problem.
Can't do it now as I've just put the glovebox back.

[OutbackAndBeyondUK]

Hi, sorry for the delay in posting but due to the bad weather I have only just fitted the cabin filter (was a bit lazy as I had a working heater).
You can see the power transistor fastened to the bottom of the motor and not fastened onto the ducting as a resistor would be.
Hope someone may find the pics useful if their motor stops working.
The pics in the earlier posts show the motor and transistor before fitting.