E92 n54 Wont jump start

Ghazikhalaf · 02-09-2019, 01:00 PM

So my car sat for 2 months while i was doing a lot of work and as you would expect after 2 months of coldness, the battery was shot. I jumped started the car and it ran and charged perfecetly fine for a 2 weeks, then i would start to get really slow cranks. I assumed the battery was going out so i changed it, one day later, it was dead again. So i jumped started it and all i would hear is click, so i replaced the starter and alternator at once and i recharged the battery. It started right away with the recharge and drove perfect. 24 hours later, i was getting off work and i went outside to warm up my car like always, it started perfect like it should, went right back inside to change. I came back out to leave and it said charging malfunction with a red battery sign. I checked the voltage on my radar dector and it said 11.5 volts while running, so the alternor was not on at all. I restarted the car and it just clicked so the battery was dead since the alternator wasnt on and it was running off the battery for 15 min. I tried both jumping from the battery and the engine post and nothing worked.

Here is what i found... while jumping the car, i took a volt meter and checked the voltage...

Big post in engine bay terminal - 14 Volts
Wire to DME from terminal - 9 Volts
Wire to Starter from terminal - 12 Volts
Batter cable to terminal - 14 Volts

I also tested the engine ground and it was fine

After playing around i hooked up the red cable straught to the starter wire post and the starter would have enough power to somewhat turn over and start but the dme dosent have power since its only getting 9 volts.

If i hooked up the positive to the dme, the car wouldnt have power to turn over but the dme will turn on.

So that means the link inside the terminal to the dme is broken

Theroys- I believe that the junction box (part 61149144884) is bad since neither the starter/alternator or dme is getting the correct power

I want other peoples input

ctuna · 02-09-2019, 03:39 PM

Ground straps are a common way to loose voltage .
The one from the engine to the chassis is usually the one
that causes the problem.

You can test for this by using one side of jumper cable between
the motor and chassis to establish a second ground connection.

Cars from places that use a lot of salt on the road or high humidity environments are more susceptible this.

Also there is a possibility of corrosion at the two power cables that go
foward to the engine bay from the cavity (bath tub ) that the battery
occupy's.

I would doubt that there would be any drop to the Junction box but
you should measure that just the same as the connector at the Junction
box had a recall for the power cable connector.

Look at this one for corrosion pictures on battery power cables

Water Drains
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showthread.php?t=1566005

https://www.e90post.com/forums/showt...&highlight=aux

https://blog.fcpeuro.com/bmw-ground-...ry-replacement

You could use the tis to look at schematic.block diagrams.
Also do you have Ista D Inpa suite for diags.

https://www.newtis.info/tisv2/a/en/

https://www.newtis.info/tisv2/a/en/e...u/search?q=DME

electical e90 pdf
http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

Ghazikhalaf · 02-09-2019, 05:33 PM

Quote:

Originally Posted by ctuna

Ground straps are a common way to loose voltage .
The one from the engine to the chassis is usually the one
that causes the problem.

You can test for this by using one side of jumper cable between
the motor and chassis to establish a second ground connection.

Cars from places that use a lot of salt on the road or high humidity environments are more susceptible this.

Also there is a possibility of corrosion at the two power cables that go
foward to the engine bay from the cavity (bath tub ) that the battery
occupy's.

I would doubt that there would be any drop to the Junction box but
you should measure that just the same as the connector at the Junction
box had a recall for the power cable connector.

Look at this one for corrosion pictures on battery power cables

Water Drains
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showthread.php?t=1566005

https://www.e90post.com/forums/showt...&highlight=aux

https://blog.fcpeuro.com/bmw-ground-...ry-replacement

You could use the tis to look at schematic.block diagrams.
Also do you have Ista D Inpa suite for diags.

https://www.newtis.info/tisv2/a/en/

https://www.newtis.info/tisv2/a/en/e...u/search?q=DME

electical e90 pdf
http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

So i test the part 61149144884 and it was fine. when i did the secondary connection, I attatched the cable to the ground connection and to the oil filter housing. The car turned over while being jump started but the dme still gets 9 volts and the battery gets 13 volts while being jumped.

ctuna · 02-09-2019, 07:56 PM

Sounds like you will need George to step in.
Sorry when you said junction box I assumed it was
the one in the Cabin.
The one in the Engine Bay looks simpler though.

There are two main power cables that come from the battery
compartment forward under the car where they terminate
in the Engine compartment I am not sure where but I would think they
would measure no voltage loss with the engine off
if you can find were they terminate.

Did you check to see that the BST at the battery is intact
if its blown or damaged so that it's open it kills the starter
circuit. It's one of the two hot lines mentioned.

Ghazikhalaf · 02-09-2019, 09:09 PM

Quote:

Originally Posted by ctuna

Sounds like you will need George to step in.
Sorry when you said junction box I assumed it was
the one in the Cabin.
The one in the Engine Bay looks simpler though.

There are two main power cables that come from the battery
compartment forward under the car where they terminate
in the Engine compartment I am not sure where but I would think they
would measure no voltage loss with the engine off
if you can find were they terminate.

Did you check to see that the BST at the battery is intact
if its blown or damaged so that it's open it kills the starter
circuit. It's one of the two hot lines mentioned.

So it was just a dead battery but thats not all. I recharged the battery again and it cranks with no start. So I had a back end flash which i flashed back to stock and mhd said the dme status was normal. After 5 cranks it turned on but surged and stalled. I got codes for exhuast and inlet camshaft synchronization, throttle, vehicle electric system and dme relay activation. The alternator didnt turn on as well. The 50 amp fuse was good in the dme box, jb4 is in map 0. HELLPPP!!

ctuna · 02-09-2019, 09:16 PM

Better talk to the people with JB4's which you might have
mentioned to start with . At least I didn't see it.

Ghazikhalaf · 02-09-2019, 09:18 PM

Quote:

Originally Posted by ctuna

Better talk to the people with JB4's which you might have
mentioned to start with . At least I didn't see it.

it isnt the jb4

gde061 · 02-09-2019, 09:43 PM

I was just reading along interested and have a kinda wild guess... perhaps all the partial cranking and turning over of the engine, you may have got something out of whack in terms of what the computer "thinks" the car should be doing, and what actual position of the engine parts are in.

I am not a mechanic, but I have a Volvo that this kind of thing happens to from time to time. I believe the memory states in the ECU get corrupted from age, and it starts going nuts. For that car, I clear out the ECU by unplugging the battery for 24 hours.

Maybe, just maybe, you can try that... or someone here might know the right procedure about how to reset the engine states in the DME properly. From what I can tell, it's probably more involved... like you probably need a BMW specific diagnostic tool.

As for the original problem, I'm sorta wondering, cause you didn't mention it, but did you register the new battery? What you were reading in terms of different voltage drops that you expected could have something to do with the computer doing it's own voltage management according to the parameters of the old battery?

Hope this may be helpful.

Ghazikhalaf · 03-04-2019, 12:15 PM

If anyone was wondering what the fix was, it was a discharged battery. got it recharged and started right away!

02-09-2019, 01:00 PM	#1
Ghazikhalaf New Member 5 Rep 24 Posts Drives: e92 335i Join Date: Dec 2018 Location: Detroit Mi iTrader: (0)	E92 n54 Wont jump start So my car sat for 2 months while i was doing a lot of work and as you would expect after 2 months of coldness, the battery was shot. I jumped started the car and it ran and charged perfecetly fine for a 2 weeks, then i would start to get really slow cranks. I assumed the battery was going out so i changed it, one day later, it was dead again. So i jumped started it and all i would hear is click, so i replaced the starter and alternator at once and i recharged the battery. It started right away with the recharge and drove perfect. 24 hours later, i was getting off work and i went outside to warm up my car like always, it started perfect like it should, went right back inside to change. I came back out to leave and it said charging malfunction with a red battery sign. I checked the voltage on my radar dector and it said 11.5 volts while running, so the alternor was not on at all. I restarted the car and it just clicked so the battery was dead since the alternator wasnt on and it was running off the battery for 15 min. I tried both jumping from the battery and the engine post and nothing worked. Here is what i found... while jumping the car, i took a volt meter and checked the voltage... Big post in engine bay terminal - 14 Volts Wire to DME from terminal - 9 Volts Wire to Starter from terminal - 12 Volts Batter cable to terminal - 14 Volts I also tested the engine ground and it was fine After playing around i hooked up the red cable straught to the starter wire post and the starter would have enough power to somewhat turn over and start but the dme dosent have power since its only getting 9 volts. If i hooked up the positive to the dme, the car wouldnt have power to turn over but the dme will turn on. So that means the link inside the terminal to the dme is broken Theroys- I believe that the junction box (part 61149144884) is bad since neither the starter/alternator or dme is getting the correct power I want other peoples input
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02-09-2019, 03:39 PM	#2
ctuna Lieutenant General 1918 Rep 13,117 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	Ground straps are a common way to loose voltage . The one from the engine to the chassis is usually the one that causes the problem. You can test for this by using one side of jumper cable between the motor and chassis to establish a second ground connection. Cars from places that use a lot of salt on the road or high humidity environments are more susceptible this. Also there is a possibility of corrosion at the two power cables that go foward to the engine bay from the cavity (bath tub ) that the battery occupy's. I would doubt that there would be any drop to the Junction box but you should measure that just the same as the connector at the Junction box had a recall for the power cable connector. Look at this one for corrosion pictures on battery power cables Water Drains https://www.e90post.com/forums/showt...hlight=battery https://www.e90post.com/forums/showt...hlight=battery https://www.e90post.com/forums/showthread.php?t=1566005 https://www.e90post.com/forums/showt...&highlight=aux https://blog.fcpeuro.com/bmw-ground-...ry-replacement You could use the tis to look at schematic.block diagrams. Also do you have Ista D Inpa suite for diags. https://www.newtis.info/tisv2/a/en/ https://www.newtis.info/tisv2/a/en/e...u/search?q=DME electical e90 pdf http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja http://www.google.com/url?sa=t&rct=j...85464276,d.cGU http://www.google.com/url?sa=t&rct=j...85464276,d.cGU Last edited by ctuna; 02-09-2019 at 05:11 PM..
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02-09-2019, 07:56 PM	#4
ctuna Lieutenant General 1918 Rep 13,117 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	Sounds like you will need George to step in. Sorry when you said junction box I assumed it was the one in the Cabin. The one in the Engine Bay looks simpler though. There are two main power cables that come from the battery compartment forward under the car where they terminate in the Engine compartment I am not sure where but I would think they would measure no voltage loss with the engine off if you can find were they terminate. Did you check to see that the BST at the battery is intact if its blown or damaged so that it's open it kills the starter circuit. It's one of the two hot lines mentioned. Last edited by ctuna; 02-09-2019 at 08:04 PM..
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02-09-2019, 09:16 PM	#6
ctuna Lieutenant General 1918 Rep 13,117 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	Better talk to the people with JB4's which you might have mentioned to start with . At least I didn't see it.
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02-09-2019, 09:43 PM	#8
gde061 Private First Class 16 Rep 103 Posts Drives: 2008 335xi coupe Join Date: Oct 2018 Location: Cleveland iTrader: (0)	I was just reading along interested and have a kinda wild guess... perhaps all the partial cranking and turning over of the engine, you may have got something out of whack in terms of what the computer "thinks" the car should be doing, and what actual position of the engine parts are in. I am not a mechanic, but I have a Volvo that this kind of thing happens to from time to time. I believe the memory states in the ECU get corrupted from age, and it starts going nuts. For that car, I clear out the ECU by unplugging the battery for 24 hours. Maybe, just maybe, you can try that... or someone here might know the right procedure about how to reset the engine states in the DME properly. From what I can tell, it's probably more involved... like you probably need a BMW specific diagnostic tool. As for the original problem, I'm sorta wondering, cause you didn't mention it, but did you register the new battery? What you were reading in terms of different voltage drops that you expected could have something to do with the computer doing it's own voltage management according to the parameters of the old battery? Hope this may be helpful.
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03-04-2019, 12:15 PM	#9
Ghazikhalaf New Member 5 Rep 24 Posts Drives: e92 335i Join Date: Dec 2018 Location: Detroit Mi iTrader: (0)	If anyone was wondering what the fix was, it was a discharged battery. got it recharged and started right away!
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