Uninstalled JB4 N54 now will not start.

Alex190hill · 12-02-2021, 11:14 PM

Today I uninstalled JB4 on my 2008 BMW 335xi (was installed when I bought)

Now I'm sitting here with a car that refuses to start and have no idea what to do or who to ask for help.

I can connect to DME and will show me codes car will crank will not start.

I should also state I forgot to disconnect battery before uninstalling. So I have no clue if I fried the ECU or DME car cranks and cranks no start.

PLEASE HELP

ky0u · 12-03-2021, 12:13 AM

Quote:

Originally Posted by Alex190hill

Today I uninstalled JB4 on my 2008 BMW 335xi (was installed when I bought)

Now I'm sitting here with a car that refuses to start and have no idea what to do or who to ask for help.

I can connect to DME and will show me codes car will crank will not start.

I should also state I forgot to disconnect battery before uninstalling. So I have no clue if I fried the ECU or DME car cranks and cranks no start.

PLEASE HELP

Was the car a standalone JB4? Any chance it may have been a hybrid set up with MHD?

Also what codes are showing up

Serf27 · 12-03-2021, 12:33 AM

There is a red wire in a pigtail connection that I believe is swapped or piggybacked when jb4 is installed. Did you put that red wire back in the oem spot?

Alex190hill · 12-03-2021, 06:00 AM

I will send codes when I get to my job I don't know what red wire you are talking about what dose it plug into what color connector?

Alex190hill · 12-03-2021, 06:05 AM

@Serf27 are you talking about the power wire that hooks into the green connector with the orange wires

Alex190hill · 12-03-2021, 06:54 AM

- DME active codes -
29F3 - DME: Fuel low-pressure sensor, electric.
2ACB - DME: DME master relay, activation.
2ACC - DME: DME master relay, shift delay.
2CF9 - DME: Throttle-valve potentiometer 1.
2CFA - DME: Throttle-valve potentiometer 2.
2D09 - DME: THROTTLE.
2E85 - BSD, message; electric coolant pump: Missing.

Alex190hill · 12-03-2021, 07:05 AM

My thought I burned something and something shorted out and it possibly is DME relay I do not know what I should check

Alex190hill · 12-03-2021, 07:06 AM

Down below

Serf27 · 12-03-2021, 11:14 AM

Quote:

Originally Posted by Alex190hill

@Serf27 are you talking about the power wire that hooks into the green connector with the orange wires

Yes I was.

Gerardo · 03-23-2023, 10:02 PM

Ever figure this out?

GnomeChild · 03-24-2023, 02:36 AM

Nope

He ended up selling the car at a loss, his dog died, his girlfriend left him, his truck threw a rod, and his house burned down

Joking aside, OP hasn't been active since last posting in this thread. I say your chances of receiving a reply from him are slim to none but other people with the same issue or have resolved this before may be able to help. I personally would have put my money on there being a BEF installed but I wouldn't be able to help you: When I removed my JB4 a few weeks ago I reverted back to MHD OEM tune and disconnected my battery before digging into my DME box for the JB4. Car started up no problem after it was all put back together, no problem. I meticulously followed a JB4 removal walkthrough on YouTube to ensure I did everything correct as it has been a while since I installed it. I guess you can interpret that as me rubbing it in your face but I'm really not, honest

Good luck

12-02-2021, 11:14 PM	#1
Alex190hill New Member 0 Rep 6 Posts Drives: 2008 bmw 335xi Join Date: Dec 2021 Location: Jackson NJ iTrader: (0)	Uninstalled JB4 N54 now will not start. Today I uninstalled JB4 on my 2008 BMW 335xi (was installed when I bought) Now I'm sitting here with a car that refuses to start and have no idea what to do or who to ask for help. I can connect to DME and will show me codes car will crank will not start. I should also state I forgot to disconnect battery before uninstalling. So I have no clue if I fried the ECU or DME car cranks and cranks no start. PLEASE HELP
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12-03-2021, 12:33 AM	#3
Serf27 Brigadier General 2851 Rep 4,322 Posts Drives: 335i Join Date: Apr 2018 Location: Sitting in a BMW. iTrader: (-1)	There is a red wire in a pigtail connection that I believe is swapped or piggybacked when jb4 is installed. Did you put that red wire back in the oem spot?
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12-03-2021, 06:00 AM	#4
Alex190hill New Member 0 Rep 6 Posts Drives: 2008 bmw 335xi Join Date: Dec 2021 Location: Jackson NJ iTrader: (0)	I will send codes when I get to my job I don't know what red wire you are talking about what dose it plug into what color connector?
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12-03-2021, 06:05 AM	#5
Alex190hill New Member 0 Rep 6 Posts Drives: 2008 bmw 335xi Join Date: Dec 2021 Location: Jackson NJ iTrader: (0)	@Serf27 are you talking about the power wire that hooks into the green connector with the orange wires
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12-03-2021, 06:54 AM	#6
Alex190hill New Member 0 Rep 6 Posts Drives: 2008 bmw 335xi Join Date: Dec 2021 Location: Jackson NJ iTrader: (0)	- DME active codes - 29F3 - DME: Fuel low-pressure sensor, electric. 2ACB - DME: DME master relay, activation. 2ACC - DME: DME master relay, shift delay. 2CF9 - DME: Throttle-valve potentiometer 1. 2CFA - DME: Throttle-valve potentiometer 2. 2D09 - DME: THROTTLE. 2E85 - BSD, message; electric coolant pump: Missing.
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12-03-2021, 07:05 AM	#7
Alex190hill New Member 0 Rep 6 Posts Drives: 2008 bmw 335xi Join Date: Dec 2021 Location: Jackson NJ iTrader: (0)	My thought I burned something and something shorted out and it possibly is DME relay I do not know what I should check
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12-03-2021, 07:06 AM	#8
Alex190hill New Member 0 Rep 6 Posts Drives: 2008 bmw 335xi Join Date: Dec 2021 Location: Jackson NJ iTrader: (0)	Here are pics Down below Attached Images
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03-23-2023, 10:02 PM	#10
Gerardo Registered 0 Rep 4 Posts Drives: 2007 550i Join Date: Feb 2023 Location: Washinton iTrader: (0)	Ever figure this out?
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03-24-2023, 02:36 AM	#11
GnomeChild IN54NE 324 Rep 483 Posts Drives: e90 335i LCI M-Sport Join Date: Feb 2018 Location: California iTrader: (3) Garage List 2010 BMW 335i [0.00]	Nope He ended up selling the car at a loss, his dog died, his girlfriend left him, his truck threw a rod, and his house burned down Joking aside, OP hasn't been active since last posting in this thread. I say your chances of receiving a reply from him are slim to none but other people with the same issue or have resolved this before may be able to help. I personally would have put my money on there being a BEF installed but I wouldn't be able to help you: When I removed my JB4 a few weeks ago I reverted back to MHD OEM tune and disconnected my battery before digging into my DME box for the JB4. Car started up no problem after it was all put back together, no problem. I meticulously followed a JB4 removal walkthrough on YouTube to ensure I did everything correct as it has been a while since I installed it. I guess you can interpret that as me rubbing it in your face but I'm really not, honest Good luck __________________
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