Blower Motor Not Running

[fourofdiamonds]

Last month I had the a/c compressor replaced on my 97 SHO. The a/c was working great until a couple of days ago.

I turned on the a/c as I was on my morning commute and the blower motor won't run. I can hear the a/c compressor kick on, checked the fuses under the hood and behind the dash and all seem ok. Ran the EATC self-test and it came back with 888, which I assume means the system is operating properly.

So today I installed a new blower motor and it still won't run. Before I take it back to the air conditioning specialist that installed the compressor, is there something else I can check?

 

[Johnlemon]

check voltage at the blower motor connector

 

[fourofdiamonds]

Thanks. Will check tonight after work. Temps in the Atlanta area are going to be over 100 for the next few days, so I want to get this fixed.

My guess is that the blower motor resistor may have gone bad. Don't want to buy the part if I don't have to, so I will run some tests. Advanced Auto wants $175 and Rock Auto $123.

It might not have been necessary to change the blower motor, but the car has 191K miles and parts are starting to wear out. The old blower motor still turned by hand fine, but there was a lot of black dust, which indicates to me that the brushes were wearing out.

 

[fourofdiamonds]

I checked again and the relay under the hood looks ok. The blower motor resistor under the dash (next to the blower motor) does not appear damaged. No power is going to the blower motor.

As I mentioned, the EATC self-test is not throwing any codes, so is something else I should check?

 

[SHOZ123]

The Gen 3 does not use a resistor. There is a Solid State motor speed controller. You need to see if you have power coming out of the blower relay. This goes to the SS speed controller and then on to the blower motor. There is also the remote climate control module that commands the SS blower motor speed controller.

 

[fourofdiamonds]

It seems that parts suppliers and the Ford parts people use different names for the same part, so it can get confusing.

What I am calling the blower motor resistor is Ford part # 19E624 which I think you are calling the solid state speed controller. Ford calls it the HVAC Blower Motor Control Unit. I have checked that part and it appears to be ok. I don't have a reliable way to test it other than my ohm meter does not give me a fault.

Can you give me the Ford part # for the remote climate control module so that I can track it down?

Thanks,

 

[SHOZ123]

Here's the RCC number and the trouble shooting chart for the '97

18C612 Remote Climate Control Module

PINPOINT TEST G: A/C BLOWER MOTOR DOES NOT RUN

G1 CHECK FUSE
Check power distribution box Fuse 11 (40A) to determine if it is good.
Is fuse good?
Yes GO to G4
No GO to G2

G2 CHECK CIRCUIT
Turn ignition switch OFF. Disconnect connector C2043 from A/C blower motor speed control. Replace power distribution box Fuse 11 (40A) and turn ignition switch to RUN. Measure voltage across Pins 1 and 2 of connector C2043 .
Is voltage greater than 9 volts?
Yes GO to G3
No CHECK Circuit 371 (PK/W) and Circuit 57 (BK) between ignition, blower motor relay and A/C blower motor speed control for high resistance and/or an open circuit. Make repairs as required.

G3 CHECK BLOWER SPEED CONTROLLER
Turn ignition switch OFF. Connect connector C2043 toA/C blower motor speed control. Turn ignition switch to RUN, press and hold FAN+ button.
Does fuse open?
Yes CHECK Circuit 371 (PK/W) for short. If not shorted REPLACE the A/C blower motor speed control.
No GO to G4

G4 CHECK WIRING
Turn ignition switch OFF. Remove speed signal wire Circuit 776 (O/BK) from blower motor speed control harness connector C2043 . Turn ignition switch to RUN with EATC system on AUTO, and press and hold FAN+ button.
Does blower motor run at high speed?
Yes GO to G5
No GO to G6

G5 CHECK FOR OPEN CIRCUIT
Check Circuit 776 (O/BK) for an open circuit. Wiggle wire while testing.
Is there 5 ohms or less?
Yes REPLACE remote climate control module.
No SERVICE Circuit 776 (O/BK). RETEST system.

G6 CHECK VOLTAGE
With Circuit 776 (O/BK) still disconnected, turn ignition switch to RUN and press and hold FAN+ button. Check voltage across blower motor speed control harness connector C215 .
Is voltage greater than 0.5 volt?
Yes CHECK blower motor.
No REPLACE if required. REPLACE A/C blower motor speed control.

PINPOINT TEST H: A/C BLOWER MOTOR RUNS CONTINUOUSLY IN HIGH SPEED

H1 CHECK BLOWER OPERATION
Turn ignition switch OFF. Disconnect harness connector C2044 from the rear of the remote climate control module. Ground connector Pin C2044 , Circuit 776 (O/BK). Then, turn ignition switch to RUN. Blower motor should not operate.
Does the blower motor operate?
Yes GO to H2
No REPLACE remote climate control module.

H2 CHECK BLOWER SPEED CONTROLLER
Turn ignition switch OFF. Reconnect harness connector C2044 to remote climate control module.
Disconnect Circuit 776 (O/BK) from A/C blower motor speed control connector Pin C2043 and reconnect connector to A/C blower motor speed control. Then, jump Pin C2043 , Circuit 57 (BK) (ground) to Pin C2043 of A/C blower motor speed control. Turn ignition switch to RUN. Blower motor should not operate.
Does blower motor operate?
Yes REPLACE A/C blower motor speed control.
No SERVICE Circuit 776 (O/BK) for open.

 

[fourofdiamonds]

Thanks - I think this will help me track down the problem.

 

[fourofdiamonds]

Ran through the test. Seems like the blower motor speed control module is bad. Tracking one down now and hope this fixes it. Thanks again for your help.

 

[fourofdiamonds]

I put in a new blower speed controller and the blower fan won't run. Any other ideas on what it could be? As previously mentioned the EATC self-test does not kick out any faults, the fuses and relay are fine. Is the remote Climate Control Module something that attached to the evaporator? Would the EATC kick out a code if it was bad? Ford lists this as a $588 part, so I want to be sure before I have to replace it.

 

[SHOZ123]

You have confirmed that the blower motor does work right?

A used RCC module should be around $25 or so.

 

[fourofdiamonds]

Blower motor is brand new from motorcraft.

 

[fourofdiamonds]

Have been searching for a used RCC - very difficult to track down.

 

[SHOZ123]

I probably have a RCC out in the hulk.

 

[fourofdiamonds]

Sounds fine. Please PM me with the details.

 

[SHOZ123]

How urgent is your need as it's in the 100Fs around here until Sunday.

 

[fourofdiamonds]

Same here. I agree working under the dash is not fun in this weather.

I have another vehicle (2005 Cadillac CTS-V) that I have been using, so I can wait a few days.

The CTS-V is a fun ride, but not fun in Atlanta traffic jams (six speed manual with skip shift). I use the SHO for my commuting to save the clutch on the CTS-V. For the moment the traffic has been lighter than normal with school out and a lot of folks on vacation, so it has been a lot less strenuous.

 

[SHOZ123]

Found the blend door actuator and motor speed control in the spar parts room. The RCC from my '97 might be loose out in the hulk. Otherwise I need to take it out of the body. of the '96.

 

[fourofdiamonds]

Thanks. When it is convenient for you works for me.

 

[fourofdiamonds]

I decided to go to PULL-A-PART and found they had 2 1996 SHOs on the lot. Both were black, one with gray interior and the other in saddle. Neither had significant body damage, so I am guessing the transmissions went bad. They usually mark the motors as bad if that is the case. Anyway, some parts had already been taken off the cars, (radios, CD players, power window motors, mirrors, etc). The interiors were somewhat torn apart, but most of the interior parts left behind. Not sure why someone would bother to do that. I removed the RCCs from both cars and picked up a few other parts. Total parts bill was about $70 for two RCCs, a couple of Solid State Spreed Controllers, a blower motor, floor mats, side marker lights and some other odds and ends. It was extremely hot, so I got what I needed and left. Going back this weekend for a few other parts that I scoped out.

Just replaced the RCC and the blower motor kicked on. It was not working as well as expected, so I did another inspection under the hood and saw that the wiring from the distributor box was beginning to fry after 190K miles. So I fixed the wiring and everything is now working great.

Thanks Paul for your help and offer for the RCC. It is a PIA to remove and install, so I am glad you did not have to do that.