Hi all,

I have been trying to troubleshoot my electrical issue all day and I have only run into dead ends, any help would be greatly appreciated. I am trying to avoid having to take my vehicle in to a shop if at all possible.

TLDR: When both the A/C Clutch Solenoid relay and the fuse are installed the A/C solenoid continues engaging and disengaging while the truck remains off draining over 3.0A from my battery while the solenoid is energized, the cycling varies about 5 to 12 minutes.

2010 Ford Ranger XLT 2WD Automatic 4.0 V6

Scenario:

Yesterday I ran into an issue where my battery was completely dead after work, and it could not be charged/jumped. On Saturday I topped off all of my fluids before my work week and noticed no issues with my battery or otherwise. When I went to jump my truck the battery only got hot and became swollen, I also noted the corrosion that had formed on the positive terminal, that wasn't there 3 days prior. I cleaned the terminal and replaced the battery that night to drive it home.

This morning the battery was at 1.4V and the positive terminal was corroded to the point that the cable terminal was disconnected from the battery terminal. I replaced the positive cable's terminal and cleaned the battery before jumping it with another car. After the battery was charged and I was able to start my truck I ran it momentarily to ensure my alternator was correctly charging the system. On shutdown of my engine I watched as my battery's charge dissipated from 12.9V down to 12.3V over approximately 30 minutes.

I measured the current draw of 3.80A while the truck was off and found the A/C Clutch Solenoid to be constantly engaging and disengaging only stopping when either the 10A fuse was pulled or the relay was removed. Removing either the fuse or the relay dropped the parasitic draw to 0.07A for approximately 25 minutes then it would drop to 0.01A I believe it may have been once the battery saver relay timed out (which I have been told is normal), removing the fuse to this circuit dropped the draw to 0.0A.

I have checked the 46A : 9L2T-14B192-AA relay to ensure it was working correctly and it is. The second the relay or the fuse are both installed the solenoid continues engaging and disengaging while the truck remains off. I have been unable to find a wiring diagram for this system, but the only thing that makes sense to me is that the relay is getting power at all times allowing the clutch to continue to cycle all day and night regardless of the truck being off. I haven't noticed any issues when driving the truck, the A/C blows cold when the **** is set to the A/C positions, and not on when the **** is in the off position.

Has anyone else experienced this, or maybe can help me find what would be providing power to this circuit when my truck is turned off?

 

Wiring diagram below

Fuse 43 in Engine Bay Fuse Box powers the AC relay's coil, but only when key is ON, test that fuse's terminals to see if it has 12v with key OFF, if so that's the issue
There are a couple of 10amp fuses for AC system, 27 in cab and 25 in engine bay, which fuse number were you pulling?

The PCM(engine computer) Grounds the AC relay to activate it when it gets AC Demand 12v from the dash Climate control switch which passes thru the 2 pressure switches to the PCM

Battery is most likely self draining if it ever got below 9volts
Do not re-charge and Disconnect either battery cable and then test battery voltage, write it down
Come back in an hour and retest two hours is better, if its lower then battery is self draining, replace it
Car batteries are not made to be drained long term, thin plates can't take it

If you re-charge a battery it will show a False higher voltage for a few hours, so can't be tested right away or it will show dropping voltage for sure
New battery will be 12.8v to 13v
3 year old battery 12.5v
5/6 year old battery 12.3v and time to shop for battery sales, this is 50% charge capacity left
12.2v and less is a done battery, replace ASAP

 

Thanks for the response,

I was pulling fuse 25 in the Engine Bay Fuse Box, and this would automatically disengage the A/C Clutch Solenoid at the A/C Compressor, with the Engine Bay Fuse Box 46A relay in the truck off and key out of the ignition.

Troubleshooting:
With the truck on and the A/C **** set to Max A/C or regular A/C and the temp **** turned to max cool, Fuse 25 only had 0.02VDC across it and the A/C would run fine.
With the truck off and the A/C **** set to Off, Fuse 25 had 0.08VDC present and the A/C solenoid was constantly clicking on and off at the A/C Compressor, about 30 second on, then 2 to 5-12 minutes off, then back on again for 30 seconds. This is when I was reading the 3.80A draw from the battery.
With the truck on and the A/C **** set to Chest/Feet and the temp **** turned to max heat, Fuse 25 had 0.02VDC present and the A/C Compressor clutch was still engaged, the cabin air was blowing hot and the A/C compressor clutch never disengaged after 5minutes, I then turned the truck off and the A/C Clutch Solenoid stayed engaged and Fuse 25 still had 0.02VDC across it, Truck off and keys out of the ignition. I pulled the 46A Engine Bay Fuse Box A/C Clutch Solenoid Relay to disengage the solenoid and waited maybe 5 minutes, put the relay back in and the A/C Clutch Solenoid instantly re-engaged.

Last night prior to making my post, I had removed the A/C Clutch Solenoid Relay, 46A Engine Bay Fuse Box, and left it out overnight. This morning I checked the battery voltage the battery was still connected at both terminals the entire night, approximately 10 hours with only the relay pulled, and the voltage read 12.20V. 10 hours earlier the voltage was 12.32V. This is all after the battery had drained Wednesday night to Thursday morning, then was recharged with a jump Thursday afternoon, as stated in my first post. This is a brand new battery purchased Wednesday night to get me home. This problem existed from my old battery I had found dead after work Wednesday night I assume from the parasitic drain that corroded my positive terminal, that battery was 4 years old and toast.

As you suggested I checked for voltage across Engine Bay Fuse Box 43 and there was 0 voltage across it, with the truck off, I pulled the fuse and verified it was still intact and reinstalled it.

This morning I re-accomplished the above mentioned Troubleshooting with the same results as yesterday. I have currently reinstalled the Engine Bay Fuse Box Relay 46A, but removed the Engine Bay Fuse Box Fuse 25 this time, to see if that will also prevent the parasitic drain for now.

I am trying to avoid having to replace the Engine Bay Fuse Box and I may even just install a battery disconnect, but I would really like to try and find a solution to this problem as I don't want to have to constantly reach under my hood to connect/disconnect the battery hah. I was really hoping it was a wire short or something simple, that I may be overlooking.

 

Looking over the wiring diagram I'm thinking that maybe Fuse 43's "S118" could be something to look at, it may be what's completing the circuit and allowing the A/C Clutch Solenoid Relay to power and close. You wouldn't happen to know what/where to find that by chance would you? haha

Also I need to find the "S117" and its ground to see if that could be the chafed, or a damaged wire that's completing the ground circuit.

worst case I guess the Clutch's coil pack could be fouled and grounding out completing the circuit, which means a new clutch assembly.

 

If pulling fuse 25 in engine bay stopped the AC relay from "clicking" the there is a short under the fuse box between fuse 25 and fuse 43 wires, the grey and the red wires
25 has 12v all the time
43 only with key on

If relays coil has 12v with key off then it could very well click on and off once computer is off

You can pull out the relay and test its slots

Ford uses two types of relays, mini-relay and micro-relay
Mini looks like this: http://www.gtsparkplugs.com/images/m...iring-840x.jpg
Micro like this: http://www.gtsparkplugs.com/images/m...lay-wiring.jpg

And ford goes back and forth with pin numbers, lol
30-87A
1 to 5

1 is 86
2 is 85
And these two are interchangeable

30 is 3
87 is 5
These two are also interchangeable in this 4 pin configuration

Any way with Relay OUT test the slots, Key OFF
Only 1 should show 12v, 30(or 87) from fuse 25

neither 1 or 2 should have 12v with key off
Turn key on
Now 1 or 2 should have 12v from fuse 43

 

Thanks again for sticking with me RonD,

The 9L2T-14B192-AA relay is a Micro 4-pin, Pins 1, 2, 3 and 5 as stated on your provided schematic for the 4.0 A/C Clutch relay.

I ran a few tests on the relay's pin slots, with the fuses installed, A/C clutch solenoid relay removed and the battery connected.

Tests:

1. Truck off / Key out / AC off / Fuses all in / Relay Out

- Fuse 39 read 12.40V at relay pin 3 (polarity reversed) positive coming from the relay and going to the fuse

- Fuse 25 read 12.40V at relay pins 5 and 2

- Fuse 43 read 12.40V at relay pin 3 (polarity reversed) positive coming from the relay and going to the fuse

2. Truck on / Key in / AC off / Fuses all in / Relay Out

- Fuse 39 read 14.10V at relay pins 5 and 1, additionally 0.02V at pin 2, additionally again 0.01V at pin 3 (polarity reversed) positive coming from the relay and going to the fuse

- Fuse 25 read 14.20V at relay pins 5 and 1, additionally 0.10V at pin 2

- Fuse 43 read 13.93V at relay pins 5 and 1, additionally 0.01V at pin 2, additionally again 0.03V at pin 3 (polarity reversed) positive coming from the relay and going to the fuse

3. Truck on / Key in / AC on / Fuses all in / Relay Out

- Fuse 39 read 14.00V at relay pins 5 and 1, additionally 0.05V at pin 2, additionally again 0.05V at pin 3 (polarity reversed) positive coming from the relay and going to the fuse

- Fuse 25 read 14.00V at relay pins 5 and 1, additionally 0.10V at pin 2

- Fuse 43 read 13.85V at relay pins 5 and 1, additionally 0.03V at pin 2, additionally again 0.03V at pin 3 (polarity reversed) positive coming from the relay and going to the fuse

I pulled the fuse box to verify there was no damage to either it or any of the wires, and found nothing remarkable. All the wires are intact, there are no damaged/pinched or missing insulation on any of the wires. The loom looks intact and undisturbed, only covered in dust as usual in Arizona. I followed the loom back to the PCM along the firewall and there are no indications of chafing or even loose supports, and the wires feeding into the PCM all appear intact, also without any damage to note.

 

I would repeat the highlitghed tests again but pull fuse 43 and put it back in during tests AN do the same for fuse 25

 

So you want me to:

1. Pull one fuse and keep it out, then pull the other momentarily then reinstall it, and check volts again then swap and repeat? Example remove fuse 25, set it aside, momentarily remove fuse 43, then reinstall fuse 45 and check voltage, with fuse 25 out, then swap the fuses and repeat.

or

2. Pull one fuse and keep it out, with the second in, check the first fuse's sockets against the relay's sockets, then swap the fuses and do it again in the second position? Example remove fuse 25, leave fuse 43 in, check the positive socket of fuse 25 against the relay, then check the connecting socket from fuse 25 to the relay.

or

3. Pull one fuse, allowing the circuit to drain, then reinstall it and re-accomplish the previous tests? Example remove fuse 25, leave fuse 43 in, 2 minutes later install fuse 25 and recheck the fuse vs the relay sockets, repeat for fuse 43.

 

key off relay out all fuses in
Test relay slots 1 and 2, neither should be 12v
If one is 12v then pull fuse 43 and retest

Key on relay out all fuses in
Test slots 3 and 5
3 should have 12v
5 should not have 12v

If 5 has 12v pull fuse 25
If 5 still has 12v then pull fuse 43

5 should never have 12v if relay is out