I bought the 2008 Mariner Hybrid with approximately 130,000 miles on it. Ordinarily I would never have bought a vehicle with such high mileage. However research indicated that many Ford Escape Hybrids go for 300,000 miles in taxi companies. Since this Mariner had all the bells and whistles i.e. backup warning, leather, 6 CD changer, etc. I went ahead and bought it. Before I did I took to the Ford dealer where I had been getting my Fiesta serviced and had them check it out. They could find nothing wrong. They also told me that they had only seen one Mariner/Escape hybrid with a bad battery and it had been struck by lightning.

At approximately 160,000 miles I went into my garage, attempted to start it and was greeted with the soon to be dreaded "STOP SAFELY NOW" warning and, of course, it wouldn't start. Towed to the dealer and advised that it had corroded relays. They charged $300+, reset the codes and all was OK for a while. A few months later and the same thing happened. This time they wanted $1400 to change the cooling fan at the bottom of the HV battery which required the battery to be pulled out. They said the fan cost $650. I searched the net and found rebuilt ones for $200. When I was told they couldn't guarantee results unless it was a Ford fan I searched again and found a Ford fan for a bit over $300. They immediately changed their tune about wanting $650. A few months later the Mariner again gave the now dreaded STOP SAFELY NOW when I went out to start it up. This time they just reset the codes and sent me on my way. Last Saturday SOS (Same Old Stuff). This time I'm told they contacted Ford with the errors they found and Ford says to change the HV battery.

From my experience with electronics in the Navy and with these Ford mechanics I have zero faith an HV battery will provide a permanent fix. I installed a new and proper car battery for it shortly after I purchased the vehicle and keep it on a trickle charger if it's going to sit for a while. The latest issue occurred after sitting my garage for a week. The Mariner now has 177,000 miles. I tried pressing the button on the driver's side door jam without any result. I bought a FORScan plug and tried to reset the few codes that it indicated were bad without success. Any suggestions?

 

I see ONE question.

"Any suggestions?"

Yes. A HUGE one. You effing have Forscan, you've read codes, tried to clear them, but you can't be bothered to tell us the **** codes?

Something I can help you with is follow the owner's manual recommendations for long term storage. They explicitly state that for cars parked 30 days or more to DISCONNECT the 12V because it can cause the HV battery to be drained. I don't entirely follow the logic, but I personally fixed a battery an '09 MMH owner left sitting with the 12V on float for 6 month. 12V was perfect, but the HV battery was DEAD DEAD DEAD, and they removed the HV jump starter for that year. It was fun. If you're going to leave the car parked for a week or more, just disconnect the 12V.

Another thing I can help you with is to let you know that YOU DON'T HAVE A CAB!. Guess what's true about cabs? They ALWAYS last longer than average passenger cars. They are operated almost continually with fewer starts and stops per mile. For hybrids, they benefit from having the A/C run all the time with the battery staying cool all the time rather than sitting in the sun and getting hot.

Your battery is to the mileage/age that you may be seeing rapid self-discharge, which is a failure mode for the Sanyo "D" cells used in the pack. With a tool like Forscan, and some sensible methodology, you can do some meaningful diagnoses.

If you want help, you need to give MEANINGFUL data. The drama of your experience isn't helpful or relevant.

 

Thanks for your prompt reply S Keith. I wasn't bothered about the codes. When you get to be as old as I am perhaps your thought processes will start to slow a bit as well. In any event here's the codes: PCM=AP1A10-FF, BCM=POA1F-20 & POA7D-60, OCS=B1318-20. Your point about taxis being constantly driven is well taken. I noticed one of the features of FORScan is the ability to equalize the charge in the various cells of the HV battery. Do you think that would be worthwhile? As I stated above I keep a trickle charger on it. I would have thought that would alleviate any discharge from the HV battery. Stiil, based on your recommendation I'll be pulling the negative lead from now on, even if it's going to sit for a few days.

 

Please double check the PCM code.

How often do you drive the vehicle?

When driven, what is the typical time/distance?

How many miles have you driven in the last 6 months?

Have most of your issues occurred after sitting for 3+ days?

 

I'm retired so I only drive it a couple of times a week, usually about 40 miles. However I take it on long trips a few times a year. It was parked for 7 days after I returned from a 15 hour trip. That's when the latest STOP SAFELY NOW warning appeared. In the past month I've probably put 2,000 miles on it. Other than that it's typically less than a 100 miles each week with 2 trips. Every time I've got that warning has been after it has been sitting my garage for less than a week, typically 3 or 4 days. However it has sat for 3 or 4 days without any problems as well. I'm off to the dealer in a few minutes to pick it up. They just reset the codes. I bought the FORScan in the hope I would be able to reset the code when it gave me the STOP SAFELY NOW message however I am unable to reset the codes with FORScan.

I have now picked up the vehicle. The service manager gave me a copy of what they sent to Ford. It's the same codes that I found. Ford says it is most likely the HV battery going bad. I have now installed a battery switch to disconnect the negative terminal on the 12v battery every time I park it. That should alleviate my suffering and aggravation. When you get old a little bit of aggravation goes a long ways. What I would really like to have is a gadget that will allow me to reset the codes myself. Anyone know of such a gadget? Also does anyone think I should run the "equalize the battery cells" process that FORScan has?

 

I'm closing in on 50 and already an intolerant old bastid (you might have guessed), so by the time I'm to retirement age, I should be the KING of intolerance to aggravation. I will spend a large portion of my day informing others to vacate my front landscaping.

The low SoC code coupled with your description of symptoms makes a failing hybrid battery my #1 diagnosis. The failure is in excessive self-discharge (they won't hold a charge anymore). Leaving the 12V connected probably doesn't have a significant influence over the 3-4 days you may leave it parked. This is typical of the Sanyo "D" cells.

Concerning hybrids, especially high mileage ones, the two cardinal sins are:

1) Heat
2) Sitting

Not sure of #1 (low risk on the models with rear air to cool the battery provided your A/C is functioning properly), but you are well into #2. A hybrid gives benefit when driven, not when sitting. If a hybrid is not going to be driven 4+ days per week, and 12K+ miles/year, it's not a good choice. 5200 miles/year on a high mileage hybrid is not good.

There is a premium cost associated with hybrids, and there is a higher maintenance risk associated with them. In most cases, fuel savings over miles driven per maintenance event does not break even.

Most of my experience has been on my 2005 FEH with the HV jumpstart and the 09 MMH that didn't have one. When you pressed the jump start button, did a light illuminate on it?

If the light illuminated, it was charging. The key is to close the door and walk away for 10 minutes to allow it to complete. If you turn the key, it terminates the HV jump. It is also helpful to have a 10A+ charger on the 12V during the HV jump process. It is also helpful to do it twice.

Disconnecting the 12V each time is probably not the solution; however, the quick disconnect will have use if you park it for 7 days or more. I BELIEVE the 12V disconnect during storage is to stop the car from monitoring the battery voltages. If the BCM is powered even in the off state, it may slowly drain the HV battery through module voltage monitoring. This is my theory, and it's the only reason I can believe a connected 12V could cause the HV to drain over a long period of time. I may be way off. Regardless, disconnecting every drive is probably not practical.

Here is my proposed solution:
1) if it has sat for more than 24 hours, 10 minutes before driving, press the jump button and walk away.
2) Put 12V on float charge 1-2 days per week.

Of course, this is predicated on the HV jump starter working AND your 12V battery being in excellent condition. If there is no light on the button, you should be able to see a voltage drop at the battery during the HV jump process.

NEVER attempt HV jump more than 2X in 30 minutes unless you're continuously connected to a 10A charger. Once you have made 2X attempts in 30 minutes, the 12V must be recharged.

I have never done the Forscan equalization process. If it forces the car to charge the battery to much higher states of charge than normal driving would produce, it may be very beneficial indeed. I suspect that it may require a very long period of idling in park to ensure this happens. I use the PC version, and I've never obtained the license to enable that feature, but I intend to some day.

 

Yes, the jump start light illuminated but it didn't seem to do anything that made any difference i.e. get rid of the accursed STOP SAFELY NOW warning.

I bought the battery disconnect switch on the advice of the service manager. He said it worked fine on another Ford hybrid, not an Explorer or Mariner though.

I read someplace that over time the battery cells will slightly lower their voltage levels. When this occurs the other cells will increase their levels slightly to compensate. Apparently the leveling process will equalize all the cells to their proper voltage levels thus sort of like refreshing the battery. It sounds like a good idea in theory anyway. Since FORScan included the process it probably has some merit.

Do you know of any gadget that will reset the codes so I can get rid of the STOP SAFELY NOW warning? That's what I would really like to have. I thought I was getting that with FORScan. That would avoid having to call the tow truck and wasting a day or two of screwing around with it.

 

Only clearing the codes will get rid of the SSN warning. The key is to avoid the conditions altogether.

Generally speaking Forscan is usually successful at clearing codes, but that depends on the actual device you're using to interface with the OBDII port. If it's not, a 12V disconnect for FIVE MINUTES will take care of most of them.

(1) this is correct.
(2) this is incorrect.
(3) Agreed.

Concerning #2, they do not go up to compensate. They are just going down at different rates. As the 250 cells age, they deteriorate at different rates. Each cell's self-discharge rate is independent. When you see cell divergence, it's because some are losing faster than nothers, not because others are increasing to compensate.

An equalization process forces ALL cells to higher states of charge. As that goes above 80%, charging becomes less efficient, so charging above 80% is progressively slower than below 80%. By pushing SoC higher, you are charging the higher cells less and the lower cells more even with the same current.

The HV jump starter is not designed to actually charge the battery. It is designed to impart the minimum charge necessary to permit the HV battery to start the ICE - and THEN use the motor-generator powered by the ICE to charge the HV battery to a useful range. I have experimented by starting a jump every 30 minutes for 8 hours (16-ish jump starts). The first one typically pulls high current from the 12V for a notable time with gradual taper throughout. Subsequent ones spike at the beginning but taper rapidly to a much lower current. This tells me the charger is targeting a minimum voltage instead of input. I've had severely discharged batteries spike to what would seem to be very good levels, but when start is attempted, the voltage drops like a rock. This is the one case where I saw 10+ jump starts finally push the battery to a level it could start the ICE. I noticed that about half way through the jumps, the battery voltage actually DROPPED. This is due to the phenomenon of high resistance associated with very low states of charge. A little current pushes the voltage very high when confronted with high resistance. Once the cells actually take on enough charge to be within their normal operating range (even if very low), the resistance drops and voltage doesn't go as high in response to the same charge current.

My overall hypothesis based on codes/symptoms:

• Battery is failing in excessive self-discharge typical for the Sanyo cells
• Sits of 24 hours or less may not permit the SoC to drop to error-triggering levels.
• Sits of 3+ days may permit the SoC to drop to error-triggering levels.
• Sits of 7+ days will almost certainly permit the SoC to drop to error-triggering levels.

These can be corrected by:

• 12V disconnect for 7+ day sits
• HV Jump for ALL sits greater than 24 hours (2 if greater than 7 days + 10A charger attached)
• All issues may be reversed or significantly improved via Forscan equalization process.

Other tips:

• 12V disconnect to clear SSN as required
• 1-2 times weekly 12V top-off with a trickle charger
• If the car has an "EV" mode button, DON'T USE IT.
• Don't try to keep the car in natural "EV" mode. Just drive conservatively.
• Try to park the car with the battery level as high as possible.

 

Thanks enormously for all your insight. I feel more confident about things now. However, I would still like to have a gadget that I could reset the codes with, get rid of the STOP SAFELY NOW warning and start the engine and go. The Ford place told me once that all they had to do was reset the codes and that was all it took. Thanks again.

 

It's not as simple as that. The SSN is in response to the low SoC code. It's real. You really need to address it. I understand the desire for simplicity and ease, but there is truly an underlying issue. Clearing codes followed by starting and driving normally may result in accelerated degradation.

Preventative steps like the HV jump prior to start and conducting the Forscan equalization function should go a long way in PREVENTING the SSN warning.