Hey guy's.

So i just got home from vacation and was given a list of things that have broke while i was gone.

So we just got this truck back from a local garage who was replacing some injectors.

Battery's started going dead so today i pulled the cables, Put a multimeter inline with the positive cable and battery, then started pulling fuses.

Had a 11.6 volt draw. Never got anything from pulling fuses so i pulled the black double connector that is on the starter relay, And there went my voltage draw.

So the relay has 5 wires going to it. 1 that is the trigger wire, 2 wires that go into one connector and hook onto the lower post. And then the other two are 'connected' with a black rubber molding but they aren't making contact with each other obviously, one is a small red wire and the other is a large red wire.

So where the hell does the large red and small red wires go? They attach to the main posts of the relay.

Sorry if that is hard to understand, Not very good at composing troubleshooting questions.

Also have a oil leak but that is a whole other thread

 

idaho86f150,

You should post some photos. It would help a lot to get some input here. I know its difficult to explain these kind of issues.

Rick...

 

To start, you don't check for a draw with a voltmeter. You must use an ammeter. It is hooked in series with the battery terminal and you generally want less than 50 milliamps of draw with everything in the vehicle turned off, key out, and after a half hour wait for all of the modules to go into "sleep" mode. If you do anything other than this, you are wasting your time.

As for the fender mounted relay, if you follow the large cable you will find it leads to the positive battery post. That relay stud is used as a junction block for the power feed to the fuse box and some other things. The smaller red wire on the opposite large stud is for the starter solenoid. You already know that the small stud gets power from the ignition switch in the "start" position.

 

Okie dokie here we go. I will say what i did from start to finish.

Unhooked both battery's positive cables
Hooked my fluke 83 multimeter, The red plug going to the positive post on the passenger side battery, The black plug going to the battery cable, **** set to DC volts.

With that done the meter showed 11.6V.

I then did the fuses etc etc.

When you look at the photos, you will see two wires going into a single connector, that are then hooked to the copper colored terminal, I unhooked that connector and then tightened the nut, still showed 11.6V.

Then i took off both nuts, and removed both the large and small red wires. Meter then showed 0.0V.

Now i thought i used the meter correctly, But if i didn't i am open to suggestions.

Pictures.

 

There are several battery drain / parasitic draw test walkthroughs on youtube. Some of them are actually very well done and helpful.

key words for youtube:
Test for battery drain
Parasitic draw test
etc,,,

I just found this one buried in my favorites. It's one of the better videos I've found. The fellow that made it does a great job of showing you and clearly talking you through the process and adds some technical information that some folks might find useful.

http://www.youtube.com/watch?v=jTECmj78ZOU

Rick...

 

As I stated previously, you aren't using the meter correctly. You can't use voltage settings, period. It will ALWAYS show voltage as long as something is hooked up that uses memory. Can't do it. Useless. Waste of time. You MUST use the meter's amp settings. This is exactly what it is designed to measure.

I understand the connections at the relay, I work on these vehicles daily. Reread my post to understand what they do. At this point, you shouldn't be touching them anyway.


Step by step:

Disconnect negative battery cable, both if diesel. Make sure the cable ends don't touch anything else!

Remove the bulb from the under hood light, if you have one.

Everything else connected, like it is ready to drive.

Remove key from ignition.

Make sure everything is turned off (dome light switch, power point chargers, etc.)

Open the driver's door and set the latch to the closed position, where it would be if the door was shut.

Set the meter to measure DC amps: Black lead to black "COM" terminal, Red lead to red/black "A" terminal. Set **** to "A" position (second from right??? I usually use an 88 and just going by memory here.)

Connect one lead, doesn't matter which, to the negative battery cable end. I use a Fluke alligator clip adapter, but use whatever is handy but reliable. Keep the cable end insulated from everything else!

Be careful from here on, as doing something wrong may result in a lot of sparks or a fried meter!

Momentarily take the negative cable end that has the meter lead attached, and hold it against the side of the negative terminal of the battery. It may produce a small spark when this happens, it is normal.

With the cable still touching the battery terminal, attach the other lead to the battery post. I usually use small vice grips here, but use whatever you can that will have a reliable connection.

Slowly separate the battery cable from the battery terminal.

At this point in time, the meter is connected in series and all of the power being supplied to the vehicle is flowing through the meter. Be Careful! Anything over 10 amps of current will either blow the internal fuse in the meter, or ruin the meter itself. You've been warned.

DO NOT turn on any switches, or open any doors other than the already open driver's door.

The meter will show a reading at this point, probably around 1 amp or so, but it varies.

Let the vehicle sit for at least 40 minutes just like it is. This is necessary for the modules in the vehicle to shut down.

After this wait period, the meter will show key-off draw on the system, which should be under 50 milliamps, or 0.050 on the meter. Anything over this is excessive. Track it down by removing the fuses one at a time, I usually start with the large ones under the hood, but not all years use these. When you see the current drop on the meter, that fuse is controlling the circuit with excessive draw. If it is one of the fuses for the interior fuse panel, reinstall the fuse and move to the interior panel, removing fuses one at a time again. You can also carefully disconnect the alternator connections, as the alternator may be causing the draw. It is very helpful to have a vehicle wiring book to check these circuits.

This is it in as simple, brief form as I can make it.

Don't forget to switch the meter leads back to the V/COM positions when you are done. If you try to check voltage with them in the A/COM positions you will blow the internal fuse.

 

Yes sir.

I will do this step by step in the morning.

I appreciate the help and patience.

Thank you.

 

I am playing with voltage drain on my truck as well. So far I tested that my truck will draw 50 mamps while sitting.
The liftgate controller, even in sleep mode will draw 12-14 mamp.
I started the troubleshooting because my truck could sit for 6 weeks in the summer, but it will not start after 2 weeks sitting in the winter. My conclusion so far is that winter moisture make small shorts that will drain the battery sitting for more than a week.
I do have 2 new batteries since last fall.

 

FireMe, Thank you.

Went through the fuses after doing everything you said.

Truck was sitting at 115MA after sitting for an hour.

The location number 15 fuse dropped it down to 35MA.

The number 15 is the GEM, PCM, ABS Module, Brake shift interlock and the speed control.

Do any of those have a known issue? or any idea what to check next. I remember there being a recall awhile back that had something to do with the cruise control, maybe related?

 

There was/is a cruise control recall.

Here's the FTE TBS page

Here's a thread that has a decent photo that also might help you denify the plug/harness <--courtesy of wallz

and there are many other pages here on FTE about the cruise control issue.

If you need more info try a search using "cruise control recall"

It just might help with your issue. It is actually a short issue that is caused by leaky brake fluid.

It is a painfully easy fix and easy to locate so maybe try and unplug the effected plug and see what happens.
The plug in question comes off your master cylinder. I think you'll find it very easily.

Rick...

 

Way to go FireMe, you're a real credit to the forums. Hope you hang around a while!

 

FireMe,

Thanks for the post. It would have been nice to have this a year ago when I was dealing with a parasitic battery drain, but I have it filed away along with some related information now.

Rick...

 

Tried unplugging the connector on the master cylinder and still showing 115MA

 

I'm wondering if it might be shorted in the wire/plug itself. Maybe a long shot, but wouldn't hurt to at least rule it out as part of the process.

Do you happen to know if your truck has been repaired by the recall? If you don't know for sure then maybe a visit to your local Ford service department would help. They should have access to your VIN history (Oasis Report) and know if its been repaired.

How does the plug look? Very oily/wet or clean?

Rick...

 

I would almost guarantee this truck has not gone in for the recall.

The plug was dry and the contacts were clean, no corrosion.