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The jump starting procedures are straightforward like in any vehicle. I believe the HV battery starts the engine via MG1. Is there a DC to DC converter from 12VDC to HV to charge the HV battery if it is discharged so the engine may be started?

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Nope, only MG1 and MG2 will provide the high voltage needed to charge the HV battery. The computer will not let you completely discharge the HV battery. Pretty much the only way you can do it is to store the car with a low HV charge for months without disconnecting the 12v battery. The manual is pretty clear though that a completely discharged HV battery is a warranty buster, unless caused by a warranty covered defect.

 

I believe the dealer can put a charge back in the HV pack but once the charge goes below a certain point it will not have the same capacity and life span. That's why they won't warranty it.

 

If you are going to store the car for a long period:

 

1) Charge the HV battery. You can do this by starting the car and in park press the accelerator about 1/4 to 1/2 way. The ICE will start and will charge the HV battery.

2) Disconnect the 12v battery. This disconnects the main HV connection relay. There must be some parasitic HV draw whenever this relay is engaged. This also keeps the 12v from discharging.

 

 

I think the car is supposed to be good for a year or more this way.

 

Jon

 

 

The jump starting procedures are straightforward like in any vehicle. I believe the HV battery starts the engine via MG1. Is there a DC to DC converter from 12VDC to HV to charge the HV battery if it is discharged so the engine may be started?

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Nope, only MG1 and MG2 will provide the high voltage needed to charge the HV battery. The computer will not let you completely discharge the HV battery. Pretty much the only way you can do it is to store the car with a low HV charge for months without disconnecting the 12v battery. The manual is pretty clear though that a completely discharged HV battery is a warranty buster, unless caused by a warranty covered defect.

 

I believe the dealer can put a charge back in the HV pack but once the charge goes below a certain point it will not have the same capacity and life span. That's why they won't warranty it.

 

If you are going to store the car for a long period:

 

1) Charge the HV battery. You can do this by starting the car and in park press the accelerator about 1/4 to 1/2 way. The ICE will start and will charge the HV battery.

2) Disconnect the 12v battery. This disconnects the main HV connection relay. There must be some parasitic HV draw whenever this relay is engaged. This also keeps the 12v from discharging.

 

 

I think the car is supposed to be good for a year or more this way.

 

Jon

 

 

 

OK, so here's a scenario that I am curious about.

 

It's January, -25 degrees, got some marginal gas.

Go out to the car and attempt to start.

Cranks for awhile then the computer gives up because the battery is too low, and throws a code.

Ordinarily I would put the car into a heated garage to warm up, add a can of heet to the gas and top off the tank

then "CHARGE THE BATTERY" because it ran down too low out in the cold.

Ordinarily this procedure would work fine for a normal car. For this car, I see the only option being

Tie a tow rope to the front, pull it down the road, while somebody pushes the brake pedal to cause regen-braking

then pull it back into the warm building, and try to start it. I guess the other option would be to have it

towed to a dealer, but I guess what would they do? I can hardly see this as a warranty issue.

Anybody have any other ideas? I love this car, but I am wondering how its going to like Minnesota Winters.

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I would agree with akirby, the only thing mentioned and warned against in the manual is letting the car sit for a long period without disconnecting the 12v battery. If the car drove then the computer let you do it. I suppose it wouldn't hurt to have the dealer check the computer though, maybe at the next oil change. It is better to argue about it now and explain what happened rather than a few years from now when they won't believe your story.

 

PS: Even though this is not mentioned for the Fusion, many newer cars (sports cars mostly) will void part of the warranty if the computer shows that you have run the car out of gas. I think they won't cover the fuel system if it was run dry.

 

Jon

 

 

The computer won't let you do anything to damage the vehicle. If it does then that's Ford's fault. Assuming you didn't disconnect something or override the computer (which I doubt is even possible).

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I drove 48 miles at between 70 and 80.

 

You should have tried a speed more like 55-65 to get better fuel efficiency... maybe you could have made it that extra mile or so

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There is no way for the fuel pick up to get out every bit of gas out of the tank, given that they can't make it pointy at the bottom. The fact that the car pulled over 17 gallons out is amazing.

 

So you got the 50 mile warning but were not able to go 50 miles? The warning is usually pretty adaptive, did you get it before getting on the highway?

 

I have driven it down to about 15 miles range left. I'm glad I did not go any lower.

 

Jon

 

 

Yeah, Ford claims to have a 17.5 gallon tank in the car and I was only able to get 17.2 in to the car (including fuel spilled/evaporated when filling on side of road), so I don't think it was actually out of gas, just the computer wouldn't let the engine use any more gas.

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Ok, that makes me feel better. My math showed some fuel left BUT I never knew how much could be drawn from the tank bottom. If it had been hilly you would have likely run out earlier.

 

Jon

 

 

No, I knew from previous fillups when the tank said around 0 miles to go that there was still gas left in the tank when it says 0 to E. I was always able to put about 15 - 15.5 gallons in it at that point, so I figured I could go about 60 miles more, but was planning to stop after 50 miles. I was on I-95 in South Carolina on that stretch where the only gas stations are 10-15 c per gallon more expensive, and based on the info from Travel Link I figured I could make it no problem and save about $2.50.

 

Was wrong.

 

Basically, I drove 99 miles after the 50 mile warning.

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