First Post... I searched on this topic, but I wanted to run it past the continuum before we commit to a course of action on this one.

I have a 2008 Ford Escape Hybrid that has been in the family for the last 5 years. When we bought it around 2020, it only had about 80k miles on it. We bought it mainly for my kids to drive (its now been through 2 of them), and so far it has given us exceptional service. It now has 130k miles on it, and still has the original traction battery in it.

Lately, if the car sits for more than 2 days, it won't start unless it goes through a HV battery jump cycle. The weather has been hot lately (100d plus every day), and car is parked in direct sunlight. The 12v was replaced last year.

I have access to Forscan Lite, and I pulled the following data off the car:
Stored codes:
P1A10
POA1F

Battery Energy Control Module:
Self Test complete, no error found

DEL_MOD_V 0.00V
V_PACK: 337.19
DELT_SOC 29.98%
AVG_SOC: 70.96%
BSOC: 52.10%
BATPAC_STAT: OK

Edit: these stats were all taken after I did a HV jump, and drove the car around for about a half hour.

I will admit, the gas mileage over the last few months has been progressively getting worse. Around town we only get about 25mpg.
The stats I have pulled, look ok to my uneducated eye, but the fact that the mileage is falling, and it won't stay charged for any extended period of time makes we wonder if the traction battery pack is starting to go south.

I have a new teenaged driver who will be taking over this car in a few months, and while I think he can handle having to use the jump button every once in a while, I don't really want to have to use it often.

Are there any other tests I can run using Forscan lite to get a more complete picture of the battery health?
Thanks,
--Alan

 

Del mod v of 0.00 is something I've never seen.

Do you still experience the need for a jump start if you disconnect the 12V and the HV data cable on the driver's side?

It's very common for these old Sanyo cells to fail in self-discharge, but there have been instances where the vehicle is draining it due to a suspected failure in the ignition lock module.

 

The DELTA_MOD_V is reporting a value of 0 or 0.06. I seems to jump between the two values.

 

I've just never seen 0 - where I could be concerned that it's not reading correctly. Since it's reading 0.06 periodically, it's probably fine.

Again, I would check to see if the battery discharges with the 12V and battery data cable disconnected.

After letting it sit for 2-3 days, make sure you check the BCM for battery pack voltage AND del_mod_v BEFORE starting.

 

ok, my google-fu is failing me here. Where can I access the battery data cable to disconnect it?

 

It's the large block connected to the driver's side front of the battery. 10mm socket.

 

Ok, and update after the car sitting for 24 hours (and no, I have not disconnected the 12v or data cable yet.) this is kind of my base line.

DEL_V_MOD 0.38v
V_PACK: 319.18v

So yeah, this is not looking good. I ran the Battery Balance routine in Forscan, and got my DEL_V_MOD down to 0.31v.

I then drove the car about a half an hour, and the DEL_V_MOD dropped further, alternating between 0.12 and 0.19. I also noticed the car was giving a lot more electric assist than I had noticed in a while. When I parked the car the voltage was at about 345. So that is my reference point for tomorrow.

I will let the car sit another full day, and see if the DEL_V_MOD creeps back up.

From what I am seeing now, the battery is in decline, but it still may be usable for a little longer.

 

I concur. You have cells failing in self-discharge, which is very common with these sanyo cells.

I recommend you AVOID the Rmode_Balance function. This can actually make it notably worse. Rmode balance can cause the Del_mod_v to worsen because it widens the charge gap between the cells with the lowest self-discharge and the highest self-discharge.

A grid charge to true 100% is the exception. If you can do that, that is beneficial. Rmode_balance can't drive the SoC high enough to balance cells once they diverge past a certain point.

 

I have this exact same problem with my 2008 Mercury Mariner Hybrid - after 2 days of no driving it won't start without the jump start. So I would like to clarify that when you say to disconnect the 12V and data cable do you mean the disconnect the actual 12V battery? Or the other 2 wire cable next to the data cable? Or some other cable? Inside the HVTB there is another cable right behind and to the right of the data cable that looks like a 12V battery cable. I actually tried disconnecting the 12V battery and a bunch of fuses a few years ago to stop the drain but it didn't stop it. But at that time I did not also disconnect the data cable.

I'm into my HVTB now, cover off while it's still in the rear, main contactor relay terminals and screws exposed and ready to install grid charger leads when the parts come. I ordered the Mean Well HLF-120H-C350A. From reading the many threads I think I understand this mechanical part, but I am wondering about the value or wisdom of doing deep discharges followed by 100% SOC charges to try and recover the functional range of the battery? When I got the SUV it would go a week without driving and still start, and had 40mpg, but now the gas mileage is significantly degraded and it only goes 2 days. I've read on other hybrid forms that 3-5 discharge/charge cycles annually as maintenance can recover the HVTB range. I don't want to damage it though, so is that true of OTHER high voltage batteries but NOT of this one? I have not actually seen this addressed in the threads on this vehicle so would really value some insight! And would probably benefit other readers. Thank you!

 

Disconnect the actual 12V battery.

The large plug requiring a 10mm socket on the driver's side front corner of the battery. The 2 pin connector is not relevant to this.

You either have a parasitic drain on the HV battery, or you have a battery failing in self-discharge. Neither are typically helped by charging/discharging.

Note that charging to full REQUIRES active cooling. Charging to 100% without active cooling will damage the cells.