I’ve been noticing a change in the starting note in my f150 lately and started paying more attention to the battery voltages. I’ve got a small digital voltmeter mounted. In other posts I’ve noted the stock behavior:
- 12.4v cruise
- 14.4v deceleration
- 13.5v when lights are on or AC is on the 2 highest fan speeds
- 14.4v after startup for 15-90 seconds
- 14.0v once a month for a few hours
i finally figured out that the battery settings require a newer version of forscan than what I was running. Here are a few notes.
1. i found a post on another forum, written by the engineer who wrote the BCM strategy. He said there is more mpg savings in battery management than in auto start/stop. I’ve seen a decent return on auto start/stop, so that’s pretty impressive.
2. if you know what to look for, it is perceivable when the alternator is commanded to dump 14.4 volts during deceleration. With the voltmeter indicating when it’s happening, you can get a sense for it. It does add a small but perceivable drag to the vehicle, which is rather impressive. Measured, that can be 40amps of current into the battery, which is not small - that’s 3/4 of a horsepower at the pulley, or more with losses.
ford calls for a factory target of holding the battery at 80% state of charge. It chronically runs the battery under-charged while cruising and then blasts it with current whenever you lift off the throttle. the bodycm tracks battery age, calculated state of charge, and considers case size (h6, h7, h8, wet vs agm, and cca).
with forscan, one can change the parameters, such as target state of charge, and then a large drop down list of maybe 20 different batteries in varying size/type/cca combinations. Other forums have mentioned that they don’t see much of a difference, but with the voltmeter mounted, I’ll say that the settings do make a difference. upping the state of charge target increases the time it spends at 14.4 cold start charge before shifting to regular mode (12.4 cruise / 14.4 decel). selecting a battery with greater capacity seems to do similarly.
one can disable the intelligent battery control, which pretty much locks it to 14.1v all day. This also disables auto start/stop. I decided not to do this, because I like the mpg the truck gets. That, and ford will reduce the alternator output during acceleration events. I don’t drive aggressively, but I do like how it feels overall. Realizing the feel of the alternator drag when it hits during deceleration, I decided I kinda agree with their strategy, and don’t really want to change the characteristics of the truck’s throttle feel.
i ending up playing with a few different state of charge targets, and will head to work Monday with 98% set. When I did that this weekend, it spent half an hour at 14.4 volts charging while forscan reported the calculated state of charge slowly ticking up. 98 might be too high…. True state of charge up there can take hours, in which case it may practically defeat the ”intelligent” battery management.
whether or not we agree with intelligent battery management, I was impressed with the amount of design they put into it, and how they integrated it into the feel of the engine response. They clearly did some work here.
-m
- 12.4v cruise
- 14.4v deceleration
- 13.5v when lights are on or AC is on the 2 highest fan speeds
- 14.4v after startup for 15-90 seconds
- 14.0v once a month for a few hours
i finally figured out that the battery settings require a newer version of forscan than what I was running. Here are a few notes.
1. i found a post on another forum, written by the engineer who wrote the BCM strategy. He said there is more mpg savings in battery management than in auto start/stop. I’ve seen a decent return on auto start/stop, so that’s pretty impressive.
2. if you know what to look for, it is perceivable when the alternator is commanded to dump 14.4 volts during deceleration. With the voltmeter indicating when it’s happening, you can get a sense for it. It does add a small but perceivable drag to the vehicle, which is rather impressive. Measured, that can be 40amps of current into the battery, which is not small - that’s 3/4 of a horsepower at the pulley, or more with losses.
ford calls for a factory target of holding the battery at 80% state of charge. It chronically runs the battery under-charged while cruising and then blasts it with current whenever you lift off the throttle. the bodycm tracks battery age, calculated state of charge, and considers case size (h6, h7, h8, wet vs agm, and cca).
with forscan, one can change the parameters, such as target state of charge, and then a large drop down list of maybe 20 different batteries in varying size/type/cca combinations. Other forums have mentioned that they don’t see much of a difference, but with the voltmeter mounted, I’ll say that the settings do make a difference. upping the state of charge target increases the time it spends at 14.4 cold start charge before shifting to regular mode (12.4 cruise / 14.4 decel). selecting a battery with greater capacity seems to do similarly.
one can disable the intelligent battery control, which pretty much locks it to 14.1v all day. This also disables auto start/stop. I decided not to do this, because I like the mpg the truck gets. That, and ford will reduce the alternator output during acceleration events. I don’t drive aggressively, but I do like how it feels overall. Realizing the feel of the alternator drag when it hits during deceleration, I decided I kinda agree with their strategy, and don’t really want to change the characteristics of the truck’s throttle feel.
i ending up playing with a few different state of charge targets, and will head to work Monday with 98% set. When I did that this weekend, it spent half an hour at 14.4 volts charging while forscan reported the calculated state of charge slowly ticking up. 98 might be too high…. True state of charge up there can take hours, in which case it may practically defeat the ”intelligent” battery management.
whether or not we agree with intelligent battery management, I was impressed with the amount of design they put into it, and how they integrated it into the feel of the engine response. They clearly did some work here.
-m