00 V70 Suddenly No Blower

Susans_Volvo · Post by **Susans_Volvo** » 08 Sep 2011, 20:14

The little green connector is some kind of sensor -- I asked about it, uh, yesterday? See this thread over here: https://www.matthewsvolvosite.com/forums ... =1&t=42513

Post by **jblackburn** » 08 Sep 2011, 20:43

That's the intake air temp sensor.

Hmmmm. Is the power wire to the blower hot? Perhaps try running another ground wire down from the power stage to something metal (not the airbag!)

C@lvin · Post by **C@lvin** » 09 Sep 2011, 00:41

So would I run the wire to ground to see if there is power to the blower? From where on the power stage would I run the wire?

If I unplug the blower, should I see 12V across the two wires?

Thanks.

washdup · Post by **washdup** » 09 Sep 2011, 07:46

Couldn't hurt to check/clean the ambient temp sensor. They are known to create havoc if they get dirty.

Edit: Cabin temp sensor . . . .

Post by **jblackburn** » 09 Sep 2011, 08:12

If I unplug the blower, should I see 12V across the two wires?

Variable, depending on what fan speed it's set to. Regardless, you should see voltage between the two (I'm guessing it's not getting there since the fan isn't running, but runs in the other car).

The blower resistor has 2 plugs on it - one four-pronged one coming from the ECC, and one two-pronged one heading to the blower. Both should have a ground, and that ground should be a black wire on a Volvo from what I can find. I'd find myself some bits of wire similar in size and stick them in the plug/wrap them around the terminals of the resistor - make sure they're not touching. Run the black wire to something metal.

PLEASE pull the fuse or disconnect the battery before you do this. Not sure what's still hot with the ignition off on ECC models, but I do know the MCC keeps at least one of the wires live.

Give that a go. If you've still got no dice, try the same on the blower wire side of the equation.

Electrical issues are such a pain, but at least this way, you were able to try out your components in another car and verify they work rather than just throwing [expensive!] parts at it.

Post by **jblackburn** » 09 Sep 2011, 08:39

Ok, looking at the diagrams, you're concerned with 4/31 (resistor) and 6/28 (blower)

Yellow-Brown is input signal
Violet-white is the output signal back to the ECC
Green-Red is the "hot" wire
Black is the ground from the resistor back to the climate control.

Not sure why this won't attach as a picture, but:

C@lvin · Post by **C@lvin** » 09 Sep 2011, 09:13

I assume you mean the cabin temp sensor........I have had problems with it once before when it was clogged with dust. Folks posting above didn't think that would contribute to blower failing to operate, but with everything else appearing to be OK it wouldn't hurt to check it out.

C@lvin · Post by **C@lvin** » 09 Sep 2011, 09:19

jblackburn wrote:Electrical issues are such a pain, but at least this way, you were able to try out your components in another car and verify they work rather than just throwing [expensive!] parts at it.

Amen!

Thanks for the diagram. Not sure if I will have time today, but I will study it over and dive back into it if I can get a few minutes to focus on it.

warbo · Post by **warbo** » 10 Sep 2011, 12:34

hi, i guess its a v70 version 1? or is this the newer version 2 (MORE ROUNDED SHAPE?)
if its the early one have a look at i think fuse 32? ( under the hood by the right hand hinge area) its a 25 amp white one, had a similar fault and that was the one, it blew another 25amp fuse but ran full blast with a 30 in the slot.
can be blown by a blown resister pack ( after replacing the fuse, fan only runs on max setting i.e. 12v straight through bypassing the resistors) and in total ist usually caused by
the fan bearings worn and dragging causing extra resistance in the resisters burning them out.
new resisters pack may cure it but is suspect both req if this fuse has blown.
cheers

C@lvin · Post by **C@lvin** » 10 Sep 2011, 21:25

warbo wrote:i guess its a v70 version 1? or is this the newer version 2 (MORE ROUNDED SHAPE?)
if its the early one have a look at i think fuse 32?

Yes, at least in the US, the 00 is the old body style. 2001 began the newer rounded body (P2?)

I will definately check the fuse you mentioned. Thanks.

Today I swapped all the previous mentioned parts (blower, power stage, and ECC control unit) plus the cabin temp sensor from the 98 S70 to the 00 V70. As before, they all worked fine in the S70, but the blower still will not run in the V70.

The interesting thing was that the cabin temp sensor from the V70 wouldn't run in either car, but the AC seemed to work fine with it in the S70.

Planning to try to study the electrical diagram tonight. there must be an open circuit somewhere.

00 V70 Suddenly No Blower

Re: 00 V70 Suddenly No Blower