97 Ford Ranger - Heat & AC Blower Fan stopped working?

[Laynester]

Hello Ford Mechanics at large,

I own a 97 Ford Ranger and about two weeks ago the cab blower fan (for
the Heat and A/C) started to intermittently fail. At that time when I
started the truck, I would turn on the A/C, and noticed that the fan
would "blast on" then turn off, then come back on, then off - next it
just stopped. There are no whistles or whines coming from the fan
(e.g. as if there was somthing stopping the fan blades).

1st thing checked: All fuses are good - no burnt one's found.

2nd thing checked: I purchased and replaced the inexpensive "fan
resistor" switch module from the local Ford dealer here. Turned on
truck, tested and it still fails - the fan resistor switch did not fix
this.

I know the AC is still working I can almost feel cold air coming out
the vents as I cruise down the road, there is just no "fan power" to
blow the air out.

Is there a next good step I can try to isolate this issue? I'm fairly
good with a electric DC Volt meter for a fuse box check or blower
motor fan "plug going into the blower fan motor" electrical test.

Any thoughts on a good next step check to fix this "no interior blower
fan" condition?

Best Regards,

Laynester

[SC Tom]

"Laynester" <brentro...@hotmail.com> wrote in message
news:7b8fa2e7-b6e6-4d58...@d77g2000hsb.googlegroups.com...

Was it the switch or the resistor module that you replaced? I was thinking
on the Rangers, the resistor pack was under the hood on the evaporator
housing.

It could be the fan itself that's gone on you. Mine went with virtually no
warning on my Escape. One day it started slowing down, and by the end of the
week, I had no fan at all. Didn't make any noise or anything, just died
quietly.

SC Tom

[Jeff]

I had a similar problem with my fan on my 97 Contour. I had the took
it to the dealer because there was supposed to be a recall. The
resistor was replaced as pat of the recall. THen, supposedly, the fan
switch was bad. They replaced that at my expense (around $88) and it
still didn't work. I tested the thing as I drove away from the dealer
and the fan didn't work. I immediately returned the car and told them
what the problem was. The shop manager let the mechanic know that he
is supposed to test the stuff before returning the car. The dealer
replaced the resistor for free, then. Had the guy tested the switch,
they would have tried to nail me for another resistor. As it was, I
wonder if the fan switch was ever bad.

Anyway, there are only about three or four points of failure - the
switch on the dash, the resistor, the grounding of the motor and the
wiring going to the switch and resistor.

Jeff

[Bruce L. Bergman]

On Mon, 25 Aug 2008 19:02:36 -0700 (PDT), Jeff wrote:
>On Aug 25, 9:54 am, Laynester <brentrobert...@hotmail.com> wrote:

>> I own a 97 Ford Ranger and about two weeks ago the cab blower fan (for
>> the Heat and A/C) started to intermittently fail. At that time when I
>> started the truck, I would turn on the A/C, and noticed that the fan
>> would "blast on" then turn off, then come back on, then off - next it
>> just stopped. There are no whistles or whines coming from the fan
>> (e.g. as if there was somthing stopping the fan blades).
>>
>> 1st thing checked: All fuses are good - no burnt one's found.
>>
>> 2nd thing checked: I purchased and replaced the inexpensive "fan
>> resistor" switch module from the local Ford dealer here. Turned on
>> truck, tested and it still fails - the fan resistor switch did not fix
>> this.
>>
>> I know the AC is still working I can almost feel cold air coming out
>> the vents as I cruise down the road, there is just no "fan power" to
>> blow the air out.
>>
>> Is there a next good step I can try to isolate this issue? I'm fairly
>> good with a electric DC Volt meter for a fuse box check or blower
>> motor fan "plug going into the blower fan motor" electrical test.

Start at the fuse block and see where the voltage is getting. And
if you get voltage all the way to the motor, check the ground.

The resistor pack is the Usual Suspect, but you still always check
things first before just throwing parts at the problem - the
resistance is very low but measurable through the pack, in the one to
three ohm range - but they usually fail open which is rather obvious.

>I had a similar problem with my fan on my 97 Contour. I had the took
>it to the dealer because there was supposed to be a recall. The
>resistor was replaced as pat of the recall. THen, supposedly, the fan
>switch was bad. They replaced that at my expense (around $88) and it
>still didn't work. I tested the thing as I drove away from the dealer
>and the fan didn't work. I immediately returned the car and told them
>what the problem was. The shop manager let the mechanic know that he
>is supposed to test the stuff before returning the car. The dealer
>replaced the resistor for free, then. Had the guy tested the switch,
>they would have tried to nail me for another resistor. As it was, I
>wonder if the fan switch was ever bad.
>
>Anyway, there are only about three or four points of failure - the
>switch on the dash, the resistor, the grounding of the motor and the
>wiring going to the switch and resistor.

The motor itself does fail from worn brushes, open windings or
seized bearings. And they get mechanically blocked with leaves and
debris in the housing,. or wrapped around the motor shaft under the
fan wheel - you have to take the fan out and check for these problems.

Unplug the motor from the harness and attach a 'killer cord'
straight to the battery with a 10A fuse and an ammeter. Run it
outside the car and see what happens - NOT from the car fan circuit,
or you'll cook the resistor pack with no air flow over it.

Find the rated fan motor current draw in the service manual for your
car, and make sure you are in the right neighborhood - if the bearings
are going bad the motor running current will be high.

The heater fan usually runs from an Accessory Circuit relay
controlled by the ignition switch, or a set of ignition switch
contacts directly, but when they go bad usually lots of things die at
once and not just the heater blower.

This should get you closer.

--<< Bruce >>--

[Laynester]

>   This should get you closer.
>

>   --<< Bruce >>--- Hide quoted text -
>

To the group above, excellent info - I'm going to start working and
troubleshooting this again on this in about 2 weeks due to having to
leave town.

Bruce very helpful info m'man. Especially running the a power lead to
the motor to see if that's blown + check groundings. Keep you all
posted in a couple of weeks on this one.

Laynester

[Ricky Forrest]

My last experience with a T-Bird, was the connector from the fan to the
relay, got old, loose and was making an over-amp condition, it fried the
connector, with intermittent connect, disconnect issues, I just cut the
connector out, and spliced it with a butt connector. Works awesome now.

[Bruce L. Bergman]

If it's inline connectors, they often have to be opened to remove
and replace the motor - Better to cut it out and use .250 male tab and
female tab Nylon shrouded connectors. Because then you can pull out
the motor,replace it, etc.

If there is a bad connector body on the cable plugged into a
hard-mounted socket on the motor, snip off the bad connector body and
get a 'repair connector' at the Parts Store.

Butt splices will work, but every time you cut the wire and resplice
it you lose another 1/4" on each end - 1/2" at a minimum, 1" if you
aren't being careful to snip right at the base of the barrel. And it
doesn't take long at all before you run out of slack in the wire.

The round "Bullet" connectors get loose over time, the .250 wide tab
is a much more reliable connection.

--<< Bruce >>--

[joshuah...@gmail.com]

I guess that I am a little late to the party on this one but I was wondering something. I have a 99 ford ranger that the motor has stopped blowing.. I haven't done any investigating yet but it works sometimes and sometimes it doesn't. I had a 97 ford Taurus several years ago and the ac would work fine until you put the car in reverse then it would shut off. I found the problem to be a neutral cutoff switch. Once I replaced that it was fine. I was wondering if the 99 ford ranger has the same thing?

We had the transmission re-built last year and since then the column shifter has been acting up. It seems that when it started messing up is when the ac motor starting going in and out.. Just a thought!

[cl...@snyder.on.ca]

On Mon, 17 Jun 2013 11:03:26 -0700 (PDT), joshuah...@gmail.com
wrote:

99% chance the brushes in the blower motor are worn out or sticking.
The other 1% is a bad connection.

[Ashton Crusher]

+1

I've had those exact symptoms many times and the fix was always a new
blower motor. Last time it happened on my explorer it was a motor I'd
previously replaced with one from Autozone (with lifetime warranty). I
took it back (they had the record in their computer) and they gave me
a new motor plus about $8 because the current price was less then what
I had paid 10 years earlier.

[Geoff Welsh]

wow. That's even better than the old Craftsman commercial where the guy
gets his grandpa's hammer replaced for free.
GW

[Ashton Crusher]

On Tue, 18 Jun 2013 10:33:22 -1000, Geoff Welsh <GeeD...@some.rr.com>
wrote:

I was quite surprised. At first I thought they would giving me some
sort of prorated refund and then were going to want me to pay for the
new motor! But no.

[Guv Bob]

<joshuah...@gmail.com> wrote in message news:c233ef9a-21e3-4839...@googlegroups.com...

---

If the fan motor is turning off and on by itself, it has to be something in the wiring - a loose wire, bad electrical component or the circuit inside the fan. I would just grab the meter, put the negative lead on ground and start testing wiring junctions until you can isolate it. Sometimes, just moving wires will make or break a bad connection and help. Just don't get too jiggy with it. :O)

[Guv Bob]

"Guv Bob" <guvbo...@yahooooooooooooooo.com> wrote in message news:bICdnXmB68ghiFfM...@earthlink.com...

PS - I just saw the Crusher's posting -- that's another possibility. I always forget to check the mechanical stuff myself. Check the easy stuff outside the motor assembly first.

[cl...@snyder.on.ca]

Every ford I've seen with the problem has been one of 2 things - a
high resistance (burned ) connector in the blower circuit, or worn out
brushes in the fan motor. About 6:1 brushes over connections

[Ashton Crusher]

I've had a couple fan motors that would go on and off by themselves.
Thought it might be the wiring but in both cases it was just a worn
out fan. The brushes sometimes made contact and sometimes didn't. ...

[Kevin Bottorff]

cl...@snyder.on.ca wrote in
news:ockks85gmffqlsfrv...@4ax.com:

If you have a habit of running the fan on high a lot of the time I
would be checking the connectors on the resistor block, pretty common.
FYI I never run the fan on any of my vehicles,on high, and have never
wore a motor out yet. KB

[cl...@snyder.on.ca]

The resistor block is NOT used when on high speed - so if there is
no high speed or other speed it is NOT the resistor block - and the
motor can wear out on low speed too if it is run more or less
steadily. If a car has AC it wears out faster because it gets used
more. And I have replaced HUNDREDS of fan motors over 4 decades.
(only 1? on my own vehicle)

[Kevin Bottorff]

cl...@snyder.on.ca wrote in news:ad6ns89sc6dus55cclf3go6moc0aa9gpju@
4ax.com:

except the wire for high does run through the block connector and melting
the connector and ends is fairly common on those. That is a bushing motor
so the faster it runs the more likely it will heat the bushings and wear
them out faster. and I always ask and the ones that run the blower on
high do tend to wear them out sooner. also almost all modern cars run the
fan all the time to guarenty cabin pressure. very few have a true off.
KB

[Geoff Welsh]

the "whack test" is quite useful on worn motors
GW

[cl...@snyder.on.ca]

On Thu, 27 Jun 2013 19:15:21 +0000 (UTC), Kevin Bottorff

And the "bushings" are not the usual problem when blower motors get
intermittent and quit. It is the "brushes". Totally different parts,
totally different function. And on a ranger (at least on up to '97?
high speed TOTALLY bypasses the resistor block. The connector on the
blower motor RELAY is the most commonly overheated/damaged connector,
followed by the connector to the blower switch - the resitors and
switch are on the ground side of the motor - so to test the motor
simply see what voltage you have ACROSS the terminals of the motor
with the fan turned on (any speed) If it is 12 volts, or very close,
the problem is in the motor itself - absolutely no if's ands or buts
about it.

[cl...@snyder.on.ca]

On Thu, 27 Jun 2013 11:22:08 -1000, Geoff Welsh <GeeD...@some.rr.com>
wrote:

It works well when they are just getting intermittent - but if you
ignore it foe a week or so, it doesn't work any more.

[Ashton Crusher]

On Thu, 27 Jun 2013 11:22:08 -1000, Geoff Welsh <GeeD...@some.rr.com>
wrote:

On my last one it wasn't very successful. Whacking it did not good
but strangely, wiggling the wires did. Must have made something move
inside. Because the Whack test didn't seem to help I was not
optimistic it was just a bum motor but instead might be a wiring
problem buried somewhere. But the new motor completely eliminated the
problem.

[wildlif...@gmail.com]

Hey pal, I have a problem I seen your post on a site about the fan not working in your ranger. Did you end up finding the problem

[pa...@schoaff.org]

my blower not running....early 90's Ranger. Disconnected the power at the connection on the blower, checked for voltage....got 11+ volts. Figured the blower must be worn out. Ordered new blower, and while it was in transit, took the old one out. For fun, jumped the connections and the SOB ran fine. Reconnected connector, no joy.

I can't see any problem with the connector. The prongs clearly seem to be making connection, but the motor doesn't run.

Wasted money on a new blower, I guess, but how do I get the old one to work like it is supposed to? It has to be the connector, doesn't it? Or....is the 11+ volts an indication I'm not getting real power to the connector?

[pa...@schoaff.org]

trying, trying. The voltage on the connector keeps dropping, and the battery is running down...I can still jump the fan off the battery and get an immediate surge. I thought, perhaps, there was a broken or almost broken wire, as improbable as that might be, but extensive twisting and bending with VAmeter reading the outbput of the connector says 'no problem'. Maybe I'll replace the module in the plenum to be sure.

[Clare Snyder]

What position do you have the switch on? On high the power goes
directly to the motor unless the switch or a wire is bad. On medium
and low speeds power goes through a set of resistors..
With the motor disconnected you should have full battery voltage
across the motor terminals in eavery position because there is no load
to drop the voltage. I believe the high speed is provided by a relay
bypassing the resistors. What year,exactly, is the ranger? The 1st gen
and seconf gen Rangers may be wired differently - and even between
1993 (first year of gen2) and 1996 there are likrly differences
If it's 92-94 see the deagram here:

https://easyautodiagnostics.com/ford/3.0L/blower-motor-circuit-diagram-1
How to test the resistor is here:
https://easyautodiagnostics.com/ford/3.0L/blower-motor-resistor-test-1


The circuit is the same on 2.3 liter and 4 liter trucks as well.

[Clare Snyder]

On Wed, 6 May 2020 11:27:38 -0700 (PDT), pa...@schoaff.org wrote:

Put the shotgun away untill you have done the required tests.