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Disable MDS with trailer light tester?

Hemogoblin

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Just wondering if this is possible?

I remember friends with F150's, disabling their start/stop feature by installing one of those trailer light tester thingy's into the trailer wiring connector on their back bumper. It basically fooled the truck into thinking it was towing a trailer, and voila! It disabled the start/stop.

But would something like that prevent the MDS from enabling? I assume so, because surely MDS isn't turning on when towing? Or is it????

Thanks
 

airgas1998

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won't do a thing to disable it.....mds is based off of load on engine and other parameters...what someone needs to come up with is somehow to default the manual gear selector to engage to 8 at all times..
 

RAM Patriot

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I'm curious why you want to disable the MDS. You don't like saving fuel?

As soon as you hit the gas pedal the MDS turns off maybe a 1/2 second lag response.
 

Hemogoblin

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won't do a thing to disable it.....mds is based off of load on engine and other parameters...what someone needs to come up with is somehow to default the manual gear selector to engage to 8 at all times..

Thanks, that's what I was afraid of. Oh well....

Putting the truck in tow/haul will also disable mds so if you can figure out how to trigger that to be in constantly, that would work.

Are you sure about this? Tow mode disabling it? Because wouldn't that be the same as connecting the tester?
 

mike_ct

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I've disabled mine with a diablosport i3 and pcm swap. worth every penny. its so smooth with mds disabled.
 

_StangPGH

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With the Pedal Commander I don't notice MDS at all except for the slight change in exhaust tone. PC is the one of the best mods going for these trucks.

Sent from my SM-G950U using Tapatalk
 

mikeru82

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Are you sure about this? Tow mode disabling it? Because wouldn't that be the same as connecting the tester?
There's no way that having a tester plugged in is in any way the same as being in tow/haul mode. You can tow with the truck in normal mode. The tester puts basically the same resistive load on the circuit as having lights plugged in. If having that load plugged in puts the truck in tow/haul mode, you couldn't pull a trailer without being in tow/haul mode if you have it plugged in.

Putting the truck in tow/haul will also disable mds so if you can figure out how to trigger that to be in constantly, that would work.
Using tow/haul to disable MDS is disadvantageous compared to using the shift buttons on the steering wheel. Tow/haul mode aids the driver in controlling the additional weight by changing the shift points for the transmission. In some vehicles it also disables overdrive (not sure if Ram does that). Tow/haul is not optimized for fuel economy, so it's adversely affected even if you're not actually towing anything. Not only would you lose any fuel economy advantages of MDS, you will also experience worse fuel economy by being in tow/haul mode.
 

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