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Featured
- #461
Upfitter Wiring Harness Discussion
- OP 🔹 Cblaxx19
- Start date
Finally made time to install mine today, along with some backup lights.
Did a little more research on Youtube, for the complete removal of the fuse box, go to 2:18- hopefully this will shed more light
Does both batteries need to be disconnected to remove the fuse box?
If so, what memory or other things happen when batteries are disconnected?
Unplugging the battery causes the transmission to relearn, and sometimes you’ll have to override/reset the window bounce back for auto up. Not a big deal at all.
- Sep 26, 2021
- 2,702
- 6,800
- Navy 68
- 22 Stone Grey Tremor, Lariat, Ultimate
- Ranger 620VS, ATAK 120
Both batteries are tied to the fuse box through parallel connection. Removing one will still leave the other one in circuit. Not unplugging means you would be working with a "hot" fuse box. I would unhook both batteries for sure, if you're pulling the main fuse box. If you are pulling the upfitter fuse box up to make connections, just disconnecting the fuse box would be adequate. If you are just connecting the new wires, no need to disconnect, but be sure not to short anything, it may blow a fuse.
- Jul 30, 2023
- 2,380
- 7,653
- 2024 F350 Tremor 7.3 Godzilla - Carbon Gray
- 1985 GMC 2500 4x4 High Sierra
How does one reset the window Bounce back up?
Thanks Guys, I have no problem disconnecting the battery. It looks so much easier in the video to add the Upfitter wires purchased here with the Upfitter fuse box out.
- Aug 22, 2023
- 1,041
- 2,800
- US Army (Ret)
- 2024 F250 Tremor Agate Black Metallic 6.7 HO Lariat
- 2007 Harley FXD 2008 BMW K1200S
it certainly is easier and cleaner with the fuse box removed - after disconnecting both batteries, I removed the air cleaner box and the passenger side battery a little more disassembly 
but well worth it IMHO to have the extra room
but well worth it IMHO to have the extra roomAccording to the manual you can override the bounce back by simply holding the up window button for a few seconds. This disables the bounce back completely.
To reset the bounce back you start with the window fully up, then press and hold down until the window opens all the way, and continue to hold the button for a few seconds. Then close the window, holding the button the entire time, plus a few seconds after it stops. Then repeat this one more time down, and up.
Just installed mine and I used the battery negative.... is this ok or should I go to the firewall instead?
- Sep 26, 2021
- 2,702
- 6,800
- Navy 68
- 22 Stone Grey Tremor, Lariat, Ultimate
- Ranger 620VS, ATAK 120
Using the battery post as your ground is fine. Just make sure you have a good connection, don't use the "clamp" screw as your connection, use the connection provided for hookup.
This is in the 22 owners manual. Not sure what if any affect it will have but with all the electronics these trucks have no telling.
- Sep 26, 2021
- 2,702
- 6,800
- Navy 68
- 22 Stone Grey Tremor, Lariat, Ultimate
- Ranger 620VS, ATAK 120
Sorry, this is misleading. You can hook directly to the battery; it will not make any difference on the computers ability to monitor "battery health" which is what this statement is all about. Here's why:
*The BMS gets its information from the current sensor, also known as the Hall effect device, which is a device that measures a field around a wire to determine how much current is flowing and the direction it is flowing. (charging or discharging) It is essentially the heart of the monitoring system for the electrical charging system health. It can determine if the charge system has a fault based on how much current is drawn during operation. (With ignition on and running)
*If you have a 6.7, you have two batteries, (Or dual battery option in gasser) both batteries using Black/Violet wires to ground, ~1/0 gauge. Both are attached directly to the chassis/engine, and one smaller lead ~10 gauge, parallel on the passenger side battery, running through a Hall Effect device to monitor current draw or charge current, during operation. (Engine running) The two larger wires represent a shunt; the smaller wire is the measurement plane for the current sensor. also connected to the chassis in parallel with the two larger wires in parallel. (See schematic for visual) Heavy current flows through the large wires, a small current flows through the small wire in parallel, most likely "calibrated" to some extent to determine the current flow of the system.
*Heavy current devices are connected directly to the battery such as a winch, and perhaps some accessories like a plow, not to the chassis. They are not monitored by the current sensor.
*If your truck is not running, you can still use the battery functions like a winch, PTO, lights, etc., and the computer is not in play.
*Hooking up a high current accessory draws its current through additional wire in series if hooking up through the chassis to battery connection, essentially dropping voltage in the wires, thereby reducing the voltage at the device. (The wires essentially become resistors at high current draw.)
To avoid this occurrence, a device such as a winch is directly connected to the battery. (Here's a video of A-Rod installing a winch in a 23 YM, the wires are directly connected to the battery.
Ok, so reading the manual is always a good thing. But understanding what and why it is printed, is also essential. So why does the manual make this statement? The batteries and charge system are monitored for health over time and as maintenance to determine charge/discharge. As batteries age, they may suffer with less capacity. The computer can possibly tell when the batteries are deteriorating via the sensor (hall effect device) and determine if a battery needs to be replaced or malfunctioning. It assumes that if you draw directly from the battery, the BMS cannot determine if there is an issue with the charging system.
By the way, as a side note, there is a lot of evidence that this does not work so well. How many people have had two batteries in parallel, getting error codes, just to find out one of the batteries were low or dead when measured independently.
If the BMS does not know how much current is drawn it can't determine the health of the batteries. (Supposedly) The fact is, you can draw all kinds of current with the ignition off, start the truck, and it will replenish, and the computer won't care. But if you kill the battery, all bets are off as to what it will do.
If you add up all of the accessory current capabilities of the upfitter switches, it's a whopping 180A+ capacity. Not to mention you can add a relay and draw even more. In this case, there is no difference if you hook accessory grounds to the chassis or the battery, it is still going to draw current from both batteries and the alternator (s) will supply the necessary current required for high demands via the regulators.
The second part of the paragraph is also telling, In quotes:
"Note: If you add electrical accessories or components to your vehicle, this may adversely affect battery performance, durability, and the performance of other electrical systems on your vehicle."
Yes. Absolutely true. If the battery is drawn down, the BMS won't work right, you can cause irreparable damage to the batteries, the loss of voltage can cause the tranny to "relearn", etc. May even throw a code. But this is not the fault of the common or chassis ground, it is a fault of the battery going dead due to inability to keep up with the demand. If you run a winch and kill your battery, you will have the same issue. And the statement is assuming the BMS will read and prevent this.
Not if the engine isn't running. And certainly not in the case where a winch is in operation.
The statement is really misleading. It's all about the battery monitoring system. I really wish tech writers could clarify this stuff. You notice they don't mention the winch.
Here's a schematic of the current sensor with a single battery and the schematic of our trucks to the right. Note the difference in the ground and chassis ground connections. The chassis ground is terminated at the engine with the common ground through two large wires. Essentially the same electrical point. It will make little or no difference whether the device is hooked up to the chassis or the battery post.
Hope I didn't miss anything. It's late...
- OP 🔹
- #477
I have one harness still available and another small batch in progress. Please reach out if interested in a harness!
Cory
Cory
I just placed an order for one and then saw this post moments ago. Hopefully I squeaked my foot in the door in time, although this is not an emergency. I'm just getting ready to do numerous upfitter connections with long purchased accessories and finally going to get to all them. So glad I stumbled on this thread and your harness system for the upfitters. Can't wait to finally get my four year old truck accessorized the way I planned when new. Thanks for offering such a nice product for our awesome trucks!
Thanks for posting this. After reading the previous post by @210tremor, I was really scratching my head as I'm fully aware of dozens of accessories folks have documented on the forum over the years where they sourced current/ground directly at the battery posts reliably without issue. Your post brought me back to solid ground, and with good timing as I have put off numerous accessory installs for many months just because so many other priorities in our lives have been higher on the list.Sorry, this is misleading. You can hook directly to the battery; it will not make any difference on the computers ability to monitor "battery health" which is what this statement is all about. Here's why:
*The BMS gets its information from the current sensor, also known as the Hall effect device, which is a device that measures a field around a wire to determine how much current is flowing and the direction it is flowing. (charging or discharging) It is essentially the heart of the monitoring system for the electrical charging system health. It can determine if the charge system has a fault based on how much current is drawn during operation. (With ignition on and running)
*If you have a 6.7, you have two batteries, (Or dual battery option in gasser) both batteries using Black/Violet wires to ground, ~1/0 gauge. Both are attached directly to the chassis/engine, and one smaller lead ~10 gauge, parallel on the passenger side battery, running through a Hall Effect device to monitor current draw or charge current, during operation. (Engine running) The two larger wires represent a shunt; the smaller wire is the measurement plane for the current sensor. also connected to the chassis in parallel with the two larger wires in parallel. (See schematic for visual) Heavy current flows through the large wires, a small current flows through the small wire in parallel, most likely "calibrated" to some extent to determine the current flow of the system.
*Heavy current devices are connected directly to the battery such as a winch, and perhaps some accessories like a plow, not to the chassis. They are not monitored by the current sensor.
*If your truck is not running, you can still use the battery functions like a winch, PTO, lights, etc., and the computer is not in play.
*Hooking up a high current accessory draws its current through additional wire in series if hooking up through the chassis to battery connection, essentially dropping voltage in the wires, thereby reducing the voltage at the device. (The wires essentially become resistors at high current draw.)
To avoid this occurrence, a device such as a winch is directly connected to the battery. (Here's a video of A-Rod installing a winch in a 23 YM, the wires are directly connected to the battery.(Skip to 51:00 minutes to see hook-up) There is no ill effect of hooking directly to the battery.
Ok, so reading the manual is always a good thing. But understanding what and why it is printed, is also essential. So why does the manual make this statement? The batteries and charge system are monitored for health over time and as maintenance to determine charge/discharge. As batteries age, they may suffer with less capacity. The computer can possibly tell when the batteries are deteriorating via the sensor (hall effect device) and determine if a battery needs to be replaced or malfunctioning. It assumes that if you draw directly from the battery, the BMS cannot determine if there is an issue with the charging system.
By the way, as a side note, there is a lot of evidence that this does not work so well. How many people have had two batteries in parallel, getting error codes, just to find out one of the batteries were low or dead when measured independently.
If the BMS does not know how much current is drawn it can't determine the health of the batteries. (Supposedly) The fact is, you can draw all kinds of current with the ignition off, start the truck, and it will replenish, and the computer won't care. But if you kill the battery, all bets are off as to what it will do.
If you add up all of the accessory current capabilities of the upfitter switches, it's a whopping 180A+ capacity. Not to mention you can add a relay and draw even more. In this case, there is no difference if you hook accessory grounds to the chassis or the battery, it is still going to draw current from both batteries and the alternator (s) will supply the necessary current required for high demands via the regulators.
The second part of the paragraph is also telling, In quotes:
"Note: If you add electrical accessories or components to your vehicle, this may adversely affect battery performance, durability, and the performance of other electrical systems on your vehicle."
Yes. Absolutely true. If the battery is drawn down, the BMS won't work right, you can cause irreparable damage to the batteries, the loss of voltage can cause the tranny to "relearn", etc. May even throw a code. But this is not the fault of the common or chassis ground, it is a fault of the battery going dead due to inability to keep up with the demand. If you run a winch and kill your battery, you will have the same issue. And the statement is assuming the BMS will read and prevent this.
Not if the engine isn't running. And certainly not in the case where a winch is in operation.
The statement is really misleading. It's all about the battery monitoring system. I really wish tech writers could clarify this stuff. You notice they don't mention the winch.
Here's a schematic of the current sensor with a single battery and the schematic of our trucks to the right. Note the difference in the ground and chassis ground connections. The chassis ground is terminated at the engine with the common ground through two large wires. Essentially the same electrical point. It will make little or no difference whether the device is hooked up to the chassis or the battery post.
View attachment 202149
Hope I didn't miss anything. It's late...
As mentioned in my previous post I'm getting things in order currently to tackle my box full of truck goodies that have been languishing. I've got the ARB compressor/distribution system and Air Lift bags as a large interconnected system, along with some accessory lighting in various forms, a GMRS radio, DC to DC charger to serve both my EcoFlow Delt Pro in the back of the truck and to charge the lithium camper batteries enroute while traveling. Train horns and idle control are also on this list of projects in waiting. I'm really looking forward to some quality time with the big red girl for a few days to get this all done.
- OP 🔹
- #480
all good. you snagged the last unit. it'll ship out tomorrow.
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