Electrical issue with ford escape.

[saddlebum]

I have an issue with my daughters 2010 ford escape but trying to find electrical diagrams has proven a total waste of time. Any help here in finding or providing schematics would be great.

 

Here is the issue or combined issues Yesterday I took my daughters car to replace the heater resister. While driving it I noticed the battery light came on. I had just replaced the battery about 4 months ago which was still the original (so 9yrs old) Which I load tested first and it failed. At the same time I checked the charging system and it was fine. So yesterday when I put the voltmeter to it the voltage was at 9 volts I started the car and what you know no battery light and it is charging but next thing I notice its going right up to 16.7 volts. then down to 14.7 and then back up to 16.7. I am assuming that this alternator is regulated by the engine ECU rather than a regulator in the alternator though I am unable to find out for sure. I am also thinking since it will charge up to 16+ volts the Alt itself is Ok. So I am thinking bad or intermittent connection of ground or positive wire or battery voltage sense wire if there is one. Another thing that popped up was a sudden loss of power steering (this car has electric power steering assist) which tends to cut in and out. At the same time as the steering cuts in and out fuel gauge, tach and radio cut out and the heater doors move same as when you turn key off and on. At no time does the battery light come on at the same time even though it too cuts in and out it does so on its own schedule.

 

I did a quick voltage drop across the battery terminals and main accessible connections which checked out fine and since it started getting dark and cold outside I called it a day and decided to go inside and see if I could pull up some wiring diagrams from the internet. If I found anything at all they want you to purchase or download some app that I am not sure is trustworthy. Even the purchasable ones don't appear to guarantee that your going to get what you want. Any trustworthy sites such as auto zone just don't have the particular one I need related to my daughters car.

 

So having said all that if any one has Info I can use I would appreciate it. In the meantime I will pull on my woolly's and go out and attack this again.:snow:

[SpencerPJ]

My first thought is the alternator as well. I would suggest that you look for a Ford Escape Forum. Many times those guys are a wealth of more specific information on these gremlin of problems. Good luck!

[BlueSky]

If the voltage is regularly going to 16 volts, then I don't think the alternator is the problem. You are probably correct that the ECU is the voltage regulator. High voltage might cook the battery as well as other things.

[Marcarl]

My thoughts go to a ground strap, from the engine to the frame or the other way around, maybe even one to the body. Being it's a Ford, it could be rusted out.

[MiCarl]

My thoughts go to a ground strap, from the engine to the frame or the other way around, maybe even one to the body. Being it's a Ford, it could be rusted out.

 

Agreed. When multiple gremlins dance together a ground is the first suspect. Unfortunately one of the toughest problems to track down too......

[djh3]

Saddlebum, I have access to some wire diagrams at work. I'll see if I can copy and download tomorrow. PCM does control alternator output on most newer cars. My lead instructor wife has a newer Escape and they have had issues with the battery cables corroding inside the plastic shielding. They swell with corrosion and loose ability to flow correct current. I will agree it is sounding like a ground issue. Look that cable over and clean them up. For grins connect a jumper cable from say the battery to a engine block/ground and see if gremlins go away.

[saddlebum]

My thoughts go to a ground strap, from the engine to the frame or the other way around, maybe even one to the body. Being it's a Ford, it could be rusted out.

The car has almost no rust and I have already done a quick voltage drop across the battery terminals and main accessible connections which checked out fine. I also took apart the grounds on the fender, chassis and engine block as well as the three batt connections at the Eng comp fuse block cleaned and reconnected them.

Once done I fired the car up and despite the batt light being on, the car was charging in the 14.5 volts range. I checked the voltage at all interior fuses and they all were at 14.3 volt range.

All of a sudden the batt indicator light went out and the voltage dropped to 12.6 volts for less than a minute and then jumped to 16.5 volts. The charging voltage then started drifting between 15.5 and 16.5 from that moment on and the Battery light remained off as well.

I have not as yet disconnected the ECU to check there for corrosion as I know on many vehicles the ECU terminals can turn green or just get loose but I guess that will be my next step. That and maybe look for any ground connections I may have missed as there are a whole lot of them all over, I just concentrated on the main ones that I could get at. BTW none of this affects the way the engine starts and runs as it starts and runs like a charm.

Edited March 4, 2019 by saddlebum

[saddlebum]

Saddlebum, I have access to some wire diagrams at work. I'll see if I can copy and download tomorrow. PCM does control alternator output on most newer cars. My lead instructor wife has a newer Escape and they have had issues with the battery cables corroding inside the plastic shielding. They swell with corrosion and loose ability to flow correct current. I will agree it is sounding like a ground issue. Look that cable over and clean them up. For grins connect a jumper cable from say the battery to a engine block/ground and see if gremlins go away.

That would be a real help in trying to pinpoint the cause. As it stands right now I am just following general trouble shooting practice going over all the connections I can find but the schematics would help in not having to waste my time checking things or taking things apart I do not need to bother with.

[RDawson]

I'd start by making sure the red cable is on the phillips and black on the flat. Or is that the red handle screwdriver is positive and black negative? Oh! The insanity...........is the smoke still in the wires. ....

[Marcarl]

This is what I came up with, you might already have as well.

 

https://www.justanswer.com/ford/afth7-battery-light-alternator-not-charging.html

 

https://ca.cargurus.com/Cars/Discussion-t11828_ds553765

 

And it seems like there are some issues with electrics seizing and staying on line and so putting a drain on the battery, but then somehow shutting off and releasing the drain so the voltage goes back to normal. Do all the electrics work as they should, even windows and door lights? seats, heated seats? Check main fuse in fuse panel and battery fuse, remove to check and inspect.

[Flyinfool]

I do not know if ford plays the same game with the charging system as GM does. The charging voltage in my truck is always bouncing around from 12.6 to 16. This is "supposed" to save gas and prolong battery life by letting the truck run off the battery for a while and then charging it back up again. It freaked me out the first time I saw this happen a week after I got the truck. I thought it popped the alternator. An alternator can use 4-5 HP of engine power when it is on. I do not believe that it saves either gas or battery life. I have yet to have a battery last more than 2 years in that thing. The good part of that is the battery I have has a 3 year full replacement warranty. So every other year I get a fresh battery for free. In 10 years I have only had to pay for that very first replacement battery.

[djh3]

Shoot me an email. I have charging system diagram. But it sure dont show much. Go by and see if there are any codes set. That would be a big help. Voltage drop across battery aint really gonna tell ya much. Need to drop across from batter to engine and other ground attachements

[baylensman]

Hop over to the fordegeforum.com this seems to be a recurring issue Something about internal shorts in batteries and bad headlight sensor seems to be the most common issue. Also the 16+ volts is a little high, recommended is 15.5

 

also found this "https://www.amazon.com/Escape-Mercury-Mariner-Diagram-Original/dp/B004T67NF6/ref=sr_1_1?keywords=2010+ford+escape+wiring+diagrams&qid=1551714982&s=gateway&sr=8-1"

[saddlebum]

Shoot me an email. I have charging system diagram. But it sure dont show much. Go by and see if there are any codes set. That would be a big help. Voltage drop across battery aint really gonna tell ya much. Need to drop across from batter to engine and other ground attachements

Thanks. PM'd you my email addy. Re; voltage drop test I tested all along and across all the electrical points even across terminal to wire connections and terminal to fastener points and I get 0 volts even on the MV scale I barely get a MV of voltage drop. There is no swelling or weak points in the wiring insulation either which would normally indicate corrosion inside the cable itself something I see a lot of on trucks due to road salt and DEF fluid leaks. Of course her car does not use DEF, so that of course is ruled out. I did see the same link Marcarl sent re: the short in the Harness to the alt but keep forgetting to check that out, I was also going to use a jumper with ground ing clamps to bridge/bypass some of the cables but forgot to do that as well. Coming of darkness and cold tend to numb your brain. Me Bad.

[saddlebum]

This is what I came up with, you might already have as well.

 

https://www.justanswer.com/ford/afth7-battery-light-alternator-not-charging.html

 

https://ca.cargurus.com/Cars/Discussion-t11828_ds553765

 

And it seems like there are some issues with electrics seizing and staying on line and so putting a drain on the battery, but then somehow shutting off and releasing the drain so the voltage goes back to normal. Do all the electrics work as they should, even windows and door lights? seats, heated seats? Check main fuse in fuse panel and battery fuse, remove to check and inspect.

Mostly everything seems to work but sometimes Radio and cluster cut out same time as the steering assist and sometimes they don't. The battery light seems to cut in and out on its own time schedule and does not occur at the same time as the other issue. So far wiggle testing any wiring that I have been able to access have not yielded any results and because the issue comes and goes it adds to the difficulty of pinning it down.

[djh3]

Info e-mailed. If you got some DTC that might help.

[saddlebum]

Info e-mailed. If you got some DTC that might help.

Checked my email but nothing turned up not even in my junk folder.

[frankd]

My sister (who lives 550 miles away from here) has been having problems with her Escape overcharging the battery. What some mechanic finally found was that the wiring to the alternator had been chewed up by mice. It cost her $1500 to get it fixed because her's is a 4WD model and the alternator is near the bottom. I guess they had to lift the motor up to get to the wiring. I'm not saying yours is the same problem, just keep your eyes open for this. She has the 3.0L V-6.

 

Frank

[BratmanXj]

It cost her $1500 to get it fixed because her's is a 4WD model and the alternator is near the bottom. I guess they had to lift the motor up to get to the wiring. I'm not saying yours is the same problem, just keep your eyes open for this. She has the 3.0L V-6.

 

All 3.0L have the alternator at the bottom-rear of the engine. I replaced the Alternator about 2 yrs ago on my '06 Mariner 3.0L AWD and its something like 11hrs book time (buddy was a service writer at the time). It was a spare car at the time so I fixed it over the course of a week, get frustrated and walk away for the night and come back the next day.

 

This car also had some pretty wicked ground-strap issues a few years back. Chased it for a long time as I kept moving "down the line" as I'd fix a system. Battery cables were replaced on both this car and my mother's old '08 Mariner due to corrosion.

[djh3]

Yea my boss wife has a newer escape, but cable issues he has had fixed on warranty

[saddlebum]

Well thanks to @djh3 providing me with schematics I have been able to go over the electrical system properly but found nothing wrong electrically. In the end we decided to let the dealer have it. Well their scan tool brought up codes mine did not (mine showing that there weren't any codes). On top of that the oil leak on the timing plate was much worse than I thought. Not that I looked to closely since I was more concerned about the on again/off again electrical gremlins, she was having, that caused her steering, radio and dash, to cut out and not always at the same time. So the oil leak to me was not an immediate issue. Turns out it had a tiny pinhole leak that was squirting directly on the alternator. Now even then since I have seen hundreds of unaffected oil soaked alternators on diesel engines (specially the old 2 stroke Detroit's that leaked oil like a bottomless bucket), Plus even if the alternator was questionable and I figured I would probably end up replacing it. In no way did I figure it was directly connected to her steering issue, which did not seem to coincide with whether the alternator was charging, not charging or over charging, since it would cut out at any time during any one of those conditions. Well guess what. They changed the alternator and issue went away. If I had not been so obsessed with the steering issue and and went ahead to replace the alternator and fix the oil leak, then carried on later to look further into the steering issue, I probably would have solved the issue right off.

 

Huh Also in my feeble defense it was friggin cold outside trying to work in the driveway ,,,,,,,,,,,,,,

Edited March 19, 2019 by saddlebum

[djh3]

LOL Old Detroit's were like BSA's. If they weren't leaking oil they probably didnt have any in them.