1997 E39 528i M52 - Not Starting …

[bmwdirtracer]

Sorry, hard to keep up with such a long thread, forgot the alternator was bad. That said, the voltage regulator costs more than the alternator. I'd buy the alternator.

[Jason5driver]

Sorry, hard to keep up with such a long thread, forgot the alternator was bad. That said, the voltage regulator costs more than the alternator. I'd buy the alternator.

I plan on getting the Bosch regulator , and not paying the insane bmw price .
I measured 12 volts from the alternator , and reads 12 volts at the hot wire on the head .

INPA wouldn’t work at all , on OBD2 and with the round pin connector .
I also noticed this on Inpa …
CE3FA21A-B9DA-4140-9F7D-2C5403AD9F39.jpg
Is this supposed to say “ Ignition on “ ?

[328 Power 04]

Ignition status also depends on the quality of your kdcan cable, so I wouldn't sweat it.

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But honestly, I wouldn't swap in an alternator until you can confirm via a multimeter reading.
Since there are hundreds of INPA packs and interpretation scripts floating around, it's hard for me to trust that value output alone.

[bmwdirtracer]

I saw, in Jason's pictures, Abel, that the alternator had recorded 17+ volts, and 18+ volts, as well as some very low values, all while running. INPA can be that inaccurate?

[328 Power 04]

I saw, in Jason's pictures, Abel, that the alternator had recorded 17+ volts, and 18+ volts, as well as some very low values, all while running. INPA can be that inaccurate?

INPA scripts can be old and reading incorrect data. Since there are hundreds of packs from everyone with no standardized latest version, I don't trust it as much for that info vs. a multimeter.

BMW has so many updates on the INPA and diag scripts (to cover for mistakes, etc), but people don't check that.

[bmwdirtracer]

Thanks, my wonderful friend. You know how unfamiliar I am with INPA, and that I am reliant upon your wisdom in such matters.

When I see 18+ volts, I tend to assume someone disconnected the battery while the car was running, and fried half the computers.

Jason, please trust Abel 100%, and leave the alternator alone until you get the car running and confirm whether it's good or bad.

[328 Power 04]

I hope that's not the case, to have frying.

I don't think it's wrong to replace alternator, I would just like an extra confirmation, that's all.
It's most likely gone bad, but it's hard to tell.

[Jason5driver]

Thank you both !!!
I did order a new voltage regulator , because the alternator is original from 1996 , so I’m assuming the regulator is bad .
I do measure 12 volts from the alternator connection though .
I going to replace the ignition switch and see if that helps .
After reading , it kind of makes sense that if the ignition doesn’t work , it can’t send the signal to the DME or power to the fuel system .

[shadowpuck]

hmmm - my only thought here is if the car will crank then the ignition switch is likely working; as its what sends power to the starter....
that said, if i remember, it's relatively cheap - and, at least on e46 is easy to change so definitely worth giving it a try.....

[Jason5driver]

hmmm - my only thought here is if the car will crank then the ignition switch is likely working; as its what sends power to the starter....
that said, if i remember, it's relatively cheap - and, at least on e46 is easy to change so definitely worth giving it a try.....

Well , I am at a loss ...
I don't know what is preventing power to the plugs .
I really can't tell what is preventing the car from starting .
I cant connect to the computer to read any codes .
I am completely electrical illiterate . lol .
I ask for help from people local , and I get a sigh and / or they distract themselves and say they are busy with something else .
I ask for help from guys on chats , and there's an idea that I am wasting their time .
It's pretty frustrating .
I guess I am too old-school ? lol .
All the local car club members have newer cars , so they don't work on cars any more .

[328 Power 04]

So you were able to connect to get codes earlier (per your pictures), what changed now?

Does the tachometer register any rpm? Ideally you'd want to see that with INPA.

[Jason5driver]

So you were able to connect to get codes earlier (per your pictures), what changed now?

Does the tachometer register any rpm? Ideally you'd want to see that with INPA.

I was lucky to get it to work a couple of times .
I don't know what was magical to allow it to connect . lol .
I have been trying to read INPA and monitor the rpm's , but I still have not been able to connect , either from the OBD2 port , or the round pin connection under the hood .

[Jason5driver]

Is this the right diagram to follow ?
I’m trying to troubleshoot where the DME is not getting power at …

[Jason5driver]

Found this when opening the large trunk fuses …

[shadowpuck]

Is this the right diagram to follow ?
I’m trying to troubleshoot where the DME is not getting power at …

that's for a 328/m3, obviously - i'm not sure how similar they'll be.

do you have access to an e39 bentley manual? if not, i'll see if i can grab some pics out of the set in the shop - i just don't know if it shows an early production car.
they'll be a bit easier to follow, perhaps.

i can post up stuff from BMW WDS - it's just not as easy to do, but, happy to do it.

chris or one of the others may know the power path off top of their head....

you mentioned local club and such - roughly where are you?

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Found this when opening the large trunk fuses …

that's the bus/bar type fuses, right? if you have a meter, you can check them for continuity....

[Jason5driver]

that's for a 328/m3, obviously - i'm not sure how similar they'll be.

do you have access to an e39 bentley manual? if not, i'll see if i can grab some pics out of the set in the shop - i just don't know if it shows an early production car.
they'll be a bit easier to follow, perhaps.

i can post up stuff from BMW WDS - it's just not as easy to do, but, happy to do it.

chris or one of the others may know the power path off top of their head....

you mentioned local club and such - roughly where are you?

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that's the bus/bar type fuses, right? if you have a meter, you can check them for continuity....

Yep , going by the MS41 ….?
I have the Bentley , but not the wiring volume .
I’m in Kansas , just south of Wichita .
Yes , with the bmw CCA .
I used to live near St. Louis , in Shiloh , by Belleville .
We were stationed at Scott AFB .

Yes , these fuses are right to the left of the battery in the trunk .
I think I will spray the yucky stuff with electric spray …
I will check them with the multimeter too .
Thank you !

[shadowpuck]

in your attempts to start the car, when its cranking - does the tach register anything?
what's the current state of the CEL (check engine light) - is it still flashing, lighting up, anything?

i'll go grab some pics from the bentley.
there was a fairly active DIY presence in that chapter, but, it's been years now since i've been involved enough to know the current state....

[shadowpuck]

20220529_000000985_iOS.jpg20220528_235933366_iOS.jpg20220529_000041447_iOS.jpg

here's some power diagrams for MS41 - not sure if that's the right DME or not....

[bmwdirtracer]

The fuse #109, mentioned earlier, is one of those megafuses.

I gave the best description I could of the circuits involved, up above. I can't attach diagrams from Alldata or Mitchell; they have protected their diagrams so they don't transfer.

[Jason5driver]

A16B9323-901F-42D4-85FE-6BB7064C1053.jpeg3BE2AA2E-E7C7-4046-BEC6-74554EA9DB2D.jpeg

[bmwdirtracer]

Sorry, I don't know; they're not labelled and I'm just following a wiring diagram. But really, why not just check for 12+ volts on both sides of every fuse...after cleaning them up. And then check the five fuses in the E-box, both sides, and see if the DME plug looks corroded inside, or if there's any sign of water intrusion in the ebox? Have you unplugged the DME plug(s) yet?

[Jason5driver]

The pictures are from this thread :
https://www.bimmerfest.com/threads/p...mw-e39.679306/

Is Fuse 109 in the trunk , or under the passenger seat ?

What is this relay ?
6D1589E8-2CEE-4A09-8E55-CBC808DF9D9D.jpg

[Jason5driver]

I found this DIY by Cnn / Cn90 , to access the fuses under the front passenger side seat :
http://bimmerboard.com/forums/posts/792253

[shadowpuck]

F109, is, to my understanding, part of the bus/mega fuses in the trunk.
i agree with chris regarding just checking for power/ground.

does the tach move at all when trying to start? i didn't see if that was answered or not.

[Jason5driver]

F109, is, to my understanding, part of the bus/mega fuses in the trunk.
i agree with chris regarding just checking for power/ground.

does the tach move at all when trying to start? i didn't see if that was answered or not.

Sorry , I missed that .
No , the tach does not move when cranking the engine .
BMW-E39-Underseat-04.jpg
I believe Fuse #109 is the 3rd from the left in this picture from Cnn / Cn90's DIY .
It's a picture of the fuses under the front passenger side seat .



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Sorry, I don't know; they're not labelled and I'm just following a wiring diagram.
But really, why not just check for 12+ volts on both sides of every fuse...after cleaning them up.
And then check the five fuses in the E-box, both sides, and see if the DME plug looks corroded inside, or if there's any sign of water intrusion in the ebox?
Have you unplugged the DME plug(s) yet?

I checked the 5 fuses in the Ebox for continuity with a multimeter , and they checked-out Ok .
I cleaned and check all the mega fuses in the trunk for continuity , and they also check-out Ok .
The super large DME plug looks fine , no signs of water or corrosion .
There's 12 volts power at the round pin connection point , by ABS module .

I plan on opening up the fuses under the front passenger side seat , and see how they look , and check for continuity and power .