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Discussion Starter · #1 ·
I have a 2006 Ford Escape XLT 4WD, 2.3L 4 cylinder, automatic transmission.

High no key battery current drain. 240mA all the time.

The problem is the battery dies when the car isn't used in more than a week. Not a problem if driven every day.

I measure battery current and found drain current to be 240mA or 0.24A of constant draw. The car spec on AlldataDIY is 50mA max.

I do have a remote start installed but I removed that (pulled fuse and unplugged cable harnesses to control module) and current only dropped about 10-15mA so not enough to matter.

I did leave the car for a couple hours thinking some of the logic circuit (in the SJB) would drop in power over time as they fell into low power sleep modes. I didn't happen. When you first connect battery current spike up to 1.5A and then drops to the 240mA about 30 seconds later (when radio display goes blank). It never goes lower than this, even hours later.

I did find the current is on the two legs on the battery box served by fuse F19 and F21. If I pull both of these fuses the current falls to zero.

I am sure it isn't leakage at the alternator as well. I disconnected the wire to the alternator thinking leaky diodes/rectifiers could be the path of leaky current. It made no difference. There was no measureable leakage current through the alternator.

I then dug into this further. I found a chunk of the 240mA drain current (5X the max spec. limit) was flowing into one of the fuse circuits.

Fuse F7 (related to radio and a few other things) was about 80mA of the 240mA. So I pulled the radio and unplugged it thinking that would be a chunk of the drain. No change. So then I pulled the instrument panel. There it was an instant 80mA drop. Down to 160mA drain still 3X the max but quite a bit less than what I had.

The puzzling thing here is the instrument panel alone is drawing more than the 50mA total budget. That said the remaining current is still well over spec.

So I am starting to think the instrument panel is fine but it is being exercised by the system controller in the SJB which is causing it to draw more current. That might explain why the SJB is drawing more current as well. The mystery question is why doesn't the SJB go to sleep and minimize power drain. There must be some stimulus causing it to stay awake and consuming power. I am at a loss as to what it could be. Doors were all closed, no key in the ignition, more than 60 minutes since the car was running, ……

Any ideas? :confused:
 

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I would have said the radio, or more appropriately the radio amp. Several Mustangs have suffered this problem in the past. Yet you have shown it to be the SJB. Maybe a simple gate in the SJB is remaining closed and causing the draw. Or the timer (internal to the SJB) isn't running. If you have narrowed it to the SJB, I'm thinking that may need replacement. I am most certainly not knowing if the SJB can be broken down into modules or if it's the Lowest Replaceable Unit. I am sure JPark will know better than any of my surmises... :yes:
 

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Discussion Starter · #3 ·
Thanks for the follow up. My guess is the timer is implemented in some software running on the board rather than a discrete timer circuit. That said if the module performs 99% of its tasks properly then the CPU and basic logic is probably sound.

I am wondering if there just was a software revision I never got in the SJB or if some input is incorrect which is triggering the controller to never go into its sleep state. Since the functionality is somewhat secretive by Ford its hard to diagnose this further.
 

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The check is in the mail, Jonas.

:D

One thing about the SJB: if the internal timer stops working, the turn signals won't flash. That's why most new Fords have signals that flash at the exact same rate -- they're driven by a divide-by-x circuit/software that's driven by the timer.

Anyway, the only way to find out what's drawing the rest of this current is to pull each and every fuse, including the larger fuses in the Battery Junction Box under the hood.

And remember that the sound system on a 2006 will have two +12V supplies -- one for continuous supply, and one switched in by the ignition.

Hope this helps!
 

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Discussion Starter · #5 ·
OK an update long after the OP.

I still had problems where the car never dropped below 240mA draw. After 3-4 days the battery is flat an unable to start the car.

I tried a new test that showed something different. I unplugged all the connectors to the remote start unit and the key code emulator. I then measured battery drain and got the familiar 240mA. This time I put a wire tie on the under hood switch to simulate a closed hood (I didn't do this before, actually I didn't notice the switch before).

So I started car. Turned it off. Removed key. Locked doors and waited. 240-250mA for 30 minutes. Then at 31 minutes the current bounced a bit and dropped to 9mA. A very respectable key off current drain!! I guess my prior tests with the hood open and the hood switch detecting an open hood prevents the SJB from ever entering its lowest power state (Sleep).

So now I plugged in the remote starter and tested it. All fine, car starts up from remote as it should. I then repeated the same test as above. 31 minutes came and went the current never dropped below 240mA. It seems that just connecting the remote starter stops the SJB from being able to ratchet down to its lowest power state. Perhaps some rogue current path prevents the car from ever reverting to full sleep mode... This is why the car is draining the battery.

Buoyed with some newfound enthusiasm I tried unplugging items to see if I could trace it to a wire. First I pulled the key bypass module (FORD TRANSPONDER INTERFACE ENCRYPTED PATS 3) thinking it may load the vehicle bus in a manner that prevents full sleep. 31 minutes later still 240mA... Current never dropped. So the bypass didn't seem to be the culprit.

So I plugged it back in and then unplugged the wires (open collector switches) inside the alarm which arm and disarm the factory alarm in the Escape. 31 minutes later.. Still 240mA.. I thought maybe I was dragging these lines in a way the SJB never goes to sleep. Not so.
Then I just ran out of time. At 31 minutes per test this could take a while.

So a couple of observations.
1. Something about the remote starter is loading the car in a way to blocks sleep mode and key off current from reaching 9mA. I could live with 20-30mA but 240mA is a deal breaker.
2. Just before the SJB goes to sleep (when I unplugged the remote starter) if seem to toggle the door locks juts before going to sleep (at about 30 minutes). I wonder if this current surge is having an issue with the remote starter lines which toggle to door lock lines as well.
3. Any way to speed up this test? Waiting 31 minutes is like watching paint dry. It could take days to find the right combination. Also why did Ford make this timer sooooo long? I can't see why it isn't a minute or two….
4. I wonder of some if the remote starters open collector switches to ground would be better off they were a relay to ground with dry contacts. I wonder if there isn't some back current path in the remote starter that is playing havoc with the SJB logic. The doors are locked by toggling a pink wire to ground and unlocked by pulling the same wire to ground through a 1k ohm resistor.

Any ideas or observations welcome.
 

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Very good post detailing some good troubleshooting. I'd say you're on the right track.
I did find the current is on the two legs on the battery box served by fuse F19 and F21. If I pull both of these fuses the current falls to zero.
Maybe I missed it, but did you ever confirm these two circuits were not the culprit?

4. I wonder of some if the remote starters open collector switches to ground would be better off they were a relay to ground with dry contacts. I wonder if there isn't some back current path in the remote starter that is playing havoc with the SJB logic. The doors are locked by toggling a pink wire to ground and unlocked by pulling the same wire to ground through a 1k ohm resistor.
Also sound like the remote start could still be at fault?

Have you tried an "old school" way to find this?
Pull each one at a time, (yeah it would take quite a bit of time with the time delay factored in) until you see the amperage drop you need?
Hope it helps.
 

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Discussion Starter · #7 ·
Still searching for an answer but its my daughters car and she lives 858 miles away so it will wait a couple months before I can look at it again.

Called the tech help line of the remote starter company to see if they had heard of their remote starters causing cars to not jump down into low power sleep mode. The guy was well intended but a bit clueless. I suspect this problem is pretty common but is mis diagnosed as just higher current drain due to always on circuits of the remote starter itself.

When I can try something next I plan to disconnect door lock circuit and see if that changes things. It just seems odd the SJB causes the doors to lock just before the 31 minute timer ends. I just wonder if that is having some effect on the remote starter or vice versa. If so then I'll add isolation relays to buffer the remote starter from the car electronics.

If that doesn't work I just keep disconnecting lines to see if anyone will change the profile.
 

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Discussion Starter · #8 ·
OK finally solved the problem :clap: . It took a couple years due to car being out of state.

In the end the problem was driving the SJB door unlock input with an open collector switch from the remote starter. The SJB didn't like that. I switched to dry contacts via a relay and the problem went away. I don't have schematics of what is inside the remote starter or the SJB but I suspect the door lock and unlock outputs have more than an open collector (BJT) output and maybe have some protection such as diodes to Vcc. When the SJB goes to drop to its lowest power state at exactly 31 minutes after last activity it doesn't like what it sees when the open collector switch is connected. It is fine with a relay since in the normal state the relay is open and the inputs to the SJB see nothing.

So a few observations for others down the road:

1) Measure your key off current before you start the install. Then measure it when you are done.
2) Wait long enough for the car to reach full power down. This car was 9mA but it takes 31 minutes to get there. A side note to any Ford engineers, why do you wait 31 minutes to drop down in power? Seems an overly long period of time.... :bang:
3) Be sure to spoof the hood switch to think the hood is closed when doing your measurement. Not the switch for the remote starter, the factory one tied to the SJB. I used a wire tie to hold the switch plunger down. The SJB won;t drop to lowest power if hood switch is open.
4) I ended up with a 45mA lowest current state once the remote starter was in the circuit and using the relays for the door unlock. This more than quadruples the factory key off current (because the remote starter isn't that terrific at power management) but 45mA is better than the 230mA I was getting that drained the battery after a few days of non usage.
 

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I am sorry but I also am having some form of electrical issue with my Daughter's 2006 V6 Limited Ford Escape.

1. We have already had a replacement PCM from Circuitboard Medics.
2. New coil overs and spark plugs
3. New battery as of last night
4. Replaced fuel filter

During the battery evaluation, they said I had a current draw in the system that affected the battery.
How do I test this current draw? Keys out? Using a standard resistance meter?

What did you actually replace or fix on your daughter's unit? I didn't actually understand what was completed?

Symptoms:
Starts and occassionally dies. Starts up after a few minutes of rest.
Sometimes just cranks and then later starts.
Sometimes see the interior lights dim for a second.

This does have the upgraded speaker system.

Thanks
 
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