Quick Fix (workaround) Ford Fusion AC Evap. Sensor

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Introduction: Quick Fix (workaround) Ford Fusion AC Evap. Sensor

Workaround that avoids the replacement of the AC evaporator sensor from all Ford Fusions up to 2012. A problem that Ford should take care in guarantee considering the poor quality of the sensor used and because it is a recurring problem on several vehicles. Ford recommends the replacement of this sensor, to do that, the complete dashboard removal is mandatory. The service costs around U$ 600 and the sensor around U$ 20. Therefore, it is not cheap.

Tools:

No tools needed.

Material:

- 1 37kOhm resistor (1/8 W);

- Electric tape;

- Stanley Knife

Teacher Notes

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Step 1: Glove Box Disassembly

Disassembly of the glove box pressing it on both sides.

Step 2: Attention to the Cord!

Step 3: Connectors

Pay attention to the left connector (it may be green or blue - normally green).

Step 4: Wiring Schematics

Wires BU-BN (blue/brown) and VT-BN (violet/brown) are the wires connected to the temperature sensor (thermistor). In some cases the thermistor will open (resistance=infinite) in others it will show the problem only when moisten, it will cause the AC compressor shut down. If this is your case, the wires must be chopped off in order to guarantee the good resistance measurement. Looking the backside of the connector blue or green (wire side), the pins will be the third and fourth from left to the right on the up row. (check here: https://www.youtube.com/watch?v=imnNjh6wGo4).

Step 5: Choice of the Good Resistor

Resistor X temperature

The good resistor is shown on the chart. A 37 kOhm resistor will generate a signal equivalent to 20 Celsius and avoid the compressor to shut down. When using AC on very cold days, the evaporator may ice, in this case you have only to shut the AC off and let the ventilation working.

Step 6: Resistor Assembly

The pictures show the resistor assembled.

Step 7: Sensor Replacement

There are three good youtube videos showing the dashboard disassembly.
Shortest service time video:

Longest service time video following Ford instructions (by the book):

Workaround
on a similar vehicle (Lincoln MKZ):

7 People Made This Project!

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145 Discussions

0
bob1781
bob1781

1 year ago on Step 6

Thanks for all the info on the ac evaporator sensor problem. I installed a 37k ohm resistor between pins 13 and 14. I cut the wires going to these pins and installed it. My ac is now putting out 57 degrees and 43 on ac max. But heater blows ouside air temp, so I installed a DPDT switch so that in winter it will be hooked to evaporator senser and flip switch in summer to read through resistor. Switch is installed in glove box. Works perfect. $3 instead of $900 to Ford!

0
AbedK4
AbedK4

Reply 8 months ago

The problem I have that pin 14 is empty

0
ktpinacoma
ktpinacoma

Reply 8 months ago

Did the DPDT switch work out?

0
rick.griggs
rick.griggs

8 months ago

Tried this on my 2007 Ford Fusion that has manual environmental controls. With all the variance of cable colors and pins being used, I wasn't sure exactly which ones to use. I saw that some people with the 2006 Fusion had used the 2nd and 4th pins on the top row so I did that. I could not get the wire to come out so I ended up just pushing the wires from the transistor in as far as I could. I started up my car and was thrilled to see that my once super chilling A/C was again pushing out frigid air.

(Any tips for dislodging the wires so I can more solidly connect the resistor wires legs to the wires would be appreciated. Seems to be staying in place just fine for now.)

I noticed some people discussing concerns that they would not have a working heater in the winter or that the compressor would be running constantly and never getting a break. I assume that would only be true for cars with the automatic temperature controls. I do not see why with manual controls I would have an issue with the heater or overworking the compressor. Am I missing something?

Anyway, thanks for the info. So happy to have A/C working again.

0
AbedK4
AbedK4

Question 8 months ago on Step 4

Hello
I am trying to follow as instruct but in my car ford fusion se 2012 there is no cable in the third pin
I attach photo describing problem

1563447646462251076161931643848.jpg
0
BrianJ161
BrianJ161

10 months ago on Step 6

I couldn't find a 37k resistor, so I used a 15k and a 22k in series. Works fine cost less than 3 bucks

0
FidgetMeyer
FidgetMeyer

Reply 9 months ago

I can't find the 37k resistor either. What exactly did you mean when you said you used a 15k and 22k in series? Did you solder them end to end? Also, did it screw up your heater at all, as others have talked about? Thanks, trying to fix my kids A/C without breaking the bank.

0
Kbueller23
Kbueller23

Question 9 months ago

I have a 2012 Fusion I see how this works and all but is there a way to do this and still have heat come winter time? Also if I just slide the resistor in with the wires and pull it out when it starts to get cold will that work? Please help

0
jacobatia29
jacobatia29

Question 1 year ago

Hello,

What if I put the motorcraft evap temp sensor under the glove box and connect it to pin 13 and 15 will it work instead of the 37 k ohm, so I do not have to worry about freezing the evap or the heater not working.

Thanks

0
Kbueller23
Kbueller23

Answer 9 months ago

Did you try this and if so how did it work? Did the heat still work?

1
dg2095
dg2095

Answer 1 year ago

I'm pretty sure it would work but it's probably still going to freeze up because it's not going to get an actual system temperature reading

0
rweaverra
rweaverra

Question 10 months ago on Introduction

Any Chance this will work with a 2013 Ford Fusion Titanium?

0
JeffB343
JeffB343

11 months ago

Worked perfectly, 2008 Fusion 2.3 fwd. Great information. thanks. Jeff B

0
bob1781
bob1781

1 year ago

I spoke to soon. I put the resistor in to fix the ac problem and read a post that someone lost the heater after doing so. I put a DPDT switch in so I could run ac thru the resistor in summer and flip the switch to run thru the original sensor for the winter. The ac works fine, but not that its getting colder I find the heater is not working regardless of switch position. Any ideas?? Thanks Bob

4
bob1781
bob1781

Question 1 year ago on Step 6

my 2010 ford fusion does not have a wire in third pin from top left. Everyone says to putthe resistor between the wires on 3rd and 4th pin from the top left??

0
dsabastian
dsabastian

Question 1 year ago on Step 7

Which wires would it be for a 2008 Ford fusion

2
KentonL1
KentonL1

Question 1 year ago

I am working on 2011 fusion with 3.0 auto A/C and put a 37 kOhm resistor in line at plug and a/c worked good for 30 minutes, turned car off and restart, no problem. After shutting off for 30 minutes then restart a/c would not engage compressor also radiator cooling fan not turning but did earlier when a/c was engaged only. Whats my issue, I need help

0
KentonL1
KentonL1

Question 1 year ago on Introduction

Does the heated front left seat shutting off after a few seconds have any to do with compressor not turning on?

0
sbac05151122
sbac05151122

Question 1 year ago

OK I did the bypass and the compressor is turning but blowing hot air - what could be my other problem? It has gas in the system.