Intermittent start issue and no power to a/c clutch

[BlindViper]

So my wifes explorer has two issues. Back story we bought this used with just under 100k miles(106k) now. Had no issues for 6 months the the a/c clutch went out. So I replaced just the clutch. Worked great then failed after 2 weeks(bearing failure). So I said the hell with it and just got a new compressor. I installed it and charged the system and all was fine for 2 weeks and the wife said the a/c wasnt as cold. So I pulled the compressor connections and one of the orings had a slightly smaller cross section. So new seals and started to recharge the system....

As I started to charge I noticed the compressor wasn't engaging. So I checked the connection it was secure. I noticed playing with the harness the clutch started to engage. I pulled the compressor to check the coil and wiring. Bench tested the coil and no amount of manipulation would cause it fail. I checked the continuity of the wires back to the fuse for the power and to the relay that controls the ground. So whatever controls the clutch I guess isn't turning it on. Anyway I gave up on fixing it yesterday as I was ready to burn the whole works to the ground. In putting everything back together I arched the alternator charging wire on the low pressure line and blew a hole clean in it.

Wife had a appointment to make so I put it back together. She left made a few stops with no issues. When she went come home it wouldn't start. It would crank with no issues just wouldn't start. One of the guys tapped on the starter and finally got it going. Now obviously it was cranking and tapping on the starter did nothing. Fast forward to this morning it seems to start 10% of the time. It runs fine with no issues. I tried to spray starting fluid and did nothing more then spudder. I swapped all the relays around and to no effect. No CEL or codes.

My thoughts on the a/c clutch is to replace the a/c sensor on the high pressure line.

Anyone have thoughts on the starting issue?

 

[peterk9]

If this is for the 2002 Explorer, you've posted in the wrong sub forum (2011 - 2019 Ex.). I can move it.

Peter

 

[BlindViper]

No 2011

 

[peterk9]

No 2011

PM sent re profile. Thank you.

 

[traveler100]

Have you checked the refrigerant Low Pressure switch usually located on the dryer? You can check with a VOM. You can also jump this switch when in low pressure to see if AC clutch is working or not.

 

[sheltonfilms]

What’s your charging voltage? If you arc’d the alternator wire I’m wondering if you hurt the charging system somehow. Worth a quick check.

When you put your compressor on is it possible you pinched a wire against it and the block? If wiggling the wires made a change I would suspect an issue with the harness and it could be common with an engine management circuit.

I think you need to trace the compressor clutch wire as much as you can and do a good visual inspection.

 

[BlindViper]

I traced the wires all the way to the fuse box. Today I just replaced the a/c line. I always replace the sensor on the high side line with no effect. There is no low pressure switch on this a/c system.

 

[sheltonfilms]

These system are a little bit smarter than the cars of a couple of decades ago. Years ago you had a low pressure and cycling switch ran inline to the ac demand circuit. Computer really didn't have much control. Now it uses an actual sensor on the lines and evap temp sensor to make a calculation on when to engage the clutch.

With all electrical issues I suggest getting Forscan and see if the computer is even trying to demand the compressor be turned on. If it doesn't show this then it means something else is keeping the computer from triggering the coil. Evap sensor could be shorted/open showing below freezing temps on evap core.

PID to be looking at is ACC_CMD.

 

[BlindViper]

I can jump the relay socket and the compressor will start so I now know its what ever controls the clutch.

Do you know where the evaporator sensor is?

I fixed the starting issue or at least I think I did.

 

[sheltonfilms]

sensor is in the hvac box accessible from under the drivers side of dash. Number 6 in diagram.

 

[peterk9]

Not sure if the diagram here is of any help or not. The one I'm looking at is the 11th one. 2011-2015 Explorer Component Location Views

Peter

 

[BlindViper]

So it just magically started working.....I did nothing but go inside and pee.

 

[BlindViper]

Cycling the a/c on and off in the car seems to trigger something.

I spoke to the dealer parts guy he said his computer didnt show a evaporator temperature sensor. It did show a hheaer temperature control sensor.

Wife has to go somewhere today but I can happily say its electronic.

Thank you Peter!

 

[Donny P]

sensor is in the hvac box accessible from under the drivers side of dash. Number 6 in diagram.
View attachment 161997

Is the HVAC box you showed us also where the cabin filter is located?
I have not changed mine, probably should.

 

[sheltonfilms]

Is the HVAC box you showed us also where the cabin filter is located?
I have not changed mine, probably should.

Ford Explorer Cabin Air Filter Replacement Guide - 2011 To 2015 Model Years - Picture Illustrated Automotive Maintenance DIY Instructions

 

[BlindViper]

Is this it Shelton?
2011 FORD EXPLORER 3.5L V6 Cabin Air Temperature Sensor | RockAuto

 

[sheltonfilms]

Is this it Shelton?
2011 FORD EXPLORER 3.5L V6 Cabin Air Temperature Sensor | RockAuto

Yeah that's it but I don't suggest just throwing parts at it without using a scanner like Forscan to diagnose the issue.

What does the instrument cluster say the outside temperature is? Is it showing correctly?

 

[peterk9]

Is the HVAC box you showed us also where the cabin filter is located?
I have not changed mine, probably should.

Welcome to the Forum Donny.
The cabin air filter is behind the glove box. Here is a post I found using the 'Search' feature (upper right); Cabin Air Filter

Peter

 

[BlindViper]

Yeah that's it but I don't suggest just throwing parts at it without using a scanner like Forscan to diagnose the issue.

What does the instrument cluster say the outside temperature is? Is it showing correctly?

As it started to get winter I stopped dealing with the issue. The touch screen does show the correct temperature. I am ordering that sensor anyway. Gonna try to get the pressure sensor as well. Ill get forscan too. If that doesnt work its going to the dealer.

 

[BlindViper]

So the a/c has been working wonderfully for almost 2 years. In forscan the computer is requesting that the compressor/clutch turn on. But there is no power going to the clutch thru. There are 2 x 12v + at the relay. Pulling fuse 62 kills 1 of them, fuse 70 the other. Both 62 and 70 fuses are good and I swapped the relay. I can jump the clutch in the fuse box so I know the clutch is working. I am not the best with electrical stuff. Anyone have any thoughts what actually turns "on" the clutch?