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Discussion Starter · #1 ·
Help from gurus?

Hi everyone,

I (and my mechanic) need some help.

Two months ago I decided to change out the entire main harness on the car. The car was driving fine with all electronics working except for burned wires (and therefore ground) to alarm components such as the motion detector, horn, rear view mirror, and as well as PDC. (Long story)

My mechanic did a lot of electrical work on other cars, and was confident on replacing my 2000 M5 (11/1999 build date). So he thought no problem... :3:

Well, the new main harness was completely in (6 weeks later). Turning on the ignition, the car had all lights in the instrument cluster and the 16:9 monitor showed "BMW" logo with v24. Starting the engine resulted in couple of crank and then silenced. It's been two weeks and no luck in getting it started.

Here are some observations and things done:

0. Main harness was right part number for the build date
1. Fuse 35 in glove compartment (blower) is blown, but we don't think its the problem
2. Scan with my Peake tool resulted in few errors from table 18, but once cleared nothing came back during subsequent start crank attempts. Presumably the errors came from loose connections during the wiring put back phase.
3. Starter was diagnosed to be fine
4. Battery was full, and diagnosed to be healthy
5. Fuel pressure is fine
6. Second key with chip inside also didn't start
7. Relays are all checked fine.
8. The mechanic said while there is power to the primary electrical systems, there is none to the secondary lines (going through EWS III?)

So we suspect the EWS III Immobilizer got faulty or lost memory? But reading from posts from other BMW messageboards suggest the car would start but only to get killed by EWS. That not the case with me. The car is trying to start, with clicks and some dull high pitch, but nothing else.

I'm trying to exhaust all other possibilities before towing the car to the local $tealer.

Any words of advise, strategy, suggestions? :sad2:

thanks.
 

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Re: Help from gurus?

Sorry, I can't help. But I just wanted you to know that you have my sympathy. This sounds really sad :crying: and sounds like it has been going on for quite a while.

Good luck in getting everything resolved.
Best Wishes,
Alfred
 

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Re: Help from gurus?

There is a so called "unloader" relay connected to the ECU. I think the power to the injectors and ignition coils go through there.

Does the mechanic not have access to the circuit diagrams?

BTW, have you checked all the fuses and relays in the rear fuse panel too?

I can imagine the EWS to be designed to lock itself if disconnected.

For what it is worth, I do hope it all works out.

David
 

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Re: Help from gurus?

Wow man you got your hands full. A few questions.

Does the engine crank and not start or does it not crank at all?
Is the clutch pedal safety switch included in the main harness? Maybe out of adjustment.
And a real dumb question. Is the battery ok? A good way to check a battery is to turn the ignition to the on position (no. 2), turn on the headlights and they should stay bright for at least ten minutes. If not replace it.

I don't have any experience with the EWS III Immobilizer in BMW but I ran across a problem in a Range Rover that did a similar thing. The Immobilizer some how got out of sync with the engine control unit and wouldn't allow the starter relay to operate. You could jump the relay and get it to crank but that was it. We had it towed to the dealer to have the two computers synced up and all was well. Cost about 75 bucks.

Joe
 

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Re: Help from gurus?

The mechanic said while there is power to the primary electrical systems, there is none to the secondary lines (going through EWS III?)
Sorry I went back and read this. The junction box for the main positive battery cables is in the trunk on the passanger side of the car behind the pull down panel. Check this real good, this is where all power for the secondary circuits come from. They should all be hot all the time.

Joe
 

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Discussion Starter · #6 ·
Re: Help from gurus?

DavidS said:
There is a so called "unloader" relay connected to the ECU. I think the power to the injectors and ignition coils go through there.

Does the mechanic not have access to the circuit diagrams?

BTW, have you checked all the fuses and relays in the rear fuse panel too?

I can imagine the EWS to be designed to lock itself if disconnected.

For what it is worth, I do hope it all works out.

David
Thanks. I'll have my mechanic double check the "unloader" relay.
 

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Discussion Starter · #7 ·
Re: Help from gurus?

hudson said:
Sorry I went back and read this. The junction box for the main positive battery cables is in the trunk on the passanger side of the car behind the pull down panel. Check this real good, this is where all power for the secondary circuits come from. They should all be hot all the time.

Joe
Thanks, that's definitely worth paying a lot of attention to. Will let you know what the installer finds.
 

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Re: Help from gurus?

SandBeast said:
... except for burned wires....

(Long story)

.
I've got to ask.... (You knew someone would.)

Wha Happen?

Good luck-

A
 

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Manners, Ard, Manners! Really! ;-)

ard said:
I've got to ask.... (You knew someone would.)

Wha Happen?

Good luck-

A


David
 

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Discussion Starter · #10 ·
Re: Help from gurus?

DavidS said:
There is a so called "unloader" relay connected to the ECU. I think the power to the injectors and ignition coils go through there.

Does the mechanic not have access to the circuit diagrams?

BTW, have you checked all the fuses and relays in the rear fuse panel too?

I can imagine the EWS to be designed to lock itself if disconnected.

For what it is worth, I do hope it all works out.

David
Hi David, thanks for the tips. All relays are fine. The mechanic did bypass EWS and go to the relay and go a few "cranks" but no start.
 

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Discussion Starter · #11 ·
Re: Help from gurus?

hudson said:
Sorry I went back and read this. The junction box for the main positive battery cables is in the trunk on the passanger side of the car behind the pull down panel. Check this real good, this is where all power for the secondary circuits come from. They should all be hot all the time.

Joe
Hi Joe, I got a clarification from my mechanic. He says the secondary line that has no power is for the starter / ignition. Everywhere else is fine. Bypassing EWS and jump at the relay got a few cranks / clicks but no start.

I think the problem could be the EWS Immoblizer losing memory after two months of no power. Anyone knows how long can the EWS hold memory (of the key codes) without power connecting to it?
 

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Discussion Starter · #12 ·
Re: Help from gurus?

ard said:
I've got to ask.... (You knew someone would.)

Wha Happen?

Good luck-

A
Well, when I get a chance I'll try to document the sequence. But let just say one of the more suspicious occurrence had to be at the local dealership. I was experience lost of power after 5 minute warmup. The dealer service folks told me they placed 3 30A fuses at three fuse slots related to fuel pump. I went home and checked that each of the 3 slots were rated 10A and they put two 30A and one 25A! And that didn't solve the problem! Replacing Cam sensor per this board did! Duh!

So one of the things I will do is check the old harness on the burned spots to see if I can trace to those fuses with 30A. If so, the dealer will be hearing from me....

There are others that may be my doing, such as wiring IATS wrong the first time, but that's not likely since after wiring correction the car was fine for a long time.
 

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Re: Help from gurus?

SandBeast said:
Hi Joe, I got a clarification from my mechanic. He says the secondary line that has no power is for the starter / ignition. Everywhere else is fine. Bypassing EWS and jump at the relay got a few cranks / clicks but no start.
I'm not surprised, the EWS also sends a signal to the DME to start the fuel pump and fire the ignition. You wonder how anyone can steal one of these cars.<!--[if gte vml 1]><v:shapetype id="_x0000_t75" coordsize="21600,21600" o:spt="75" o:preferrelative="t" path="[email protected]@[email protected]@[email protected]@[email protected]@5xe" filled="f" stroked="f"> <v:stroke joinstyle="miter"/> <v:formulas> <v:f eqn="if lineDrawn pixelLineWidth 0"/> <v:f eqn="sum @0 1 0"/> <v:f eqn="sum 0 0 @1"/> <v:f eqn="prod @2 1 2"/> <v:f eqn="prod @3 21600 pixelWidth"/> <v:f eqn="prod @3 21600 pixelHeight"/> <v:f eqn="sum @0 0 1"/> <v:f eqn="prod @6 1 2"/> <v:f eqn="prod @7 21600 pixelWidth"/> <v:f eqn="sum @8 21600 0"/> <v:f eqn="prod @7 21600 pixelHeight"/> <v:f eqn="sum @10 21600 0"/> </v:formulas> <v:path o:extrusionok="f" gradientshapeok="t" o:connecttype="rect"/> <o:lock v:ext="edit" aspectratio="t"/> </v:shapetype><v:shape id="_x0000_i1025" type="#_x0000_t75" alt="" style='width:11.25pt; height:11.25pt'> <v:imagedata src="file:///C:/DOCUME~1/JMS/LOCALS~1/Temp/msoclip1/01/clip_image001.gif" o:href="http://www.m5board.com/ubb/rolleyes.gif"/> </v:shape><![endif]--><!--[if !vml]--> :rolleyes:<!--[endif]-->


I think the problem could be the EWS Immobilizer losing memory after two months of no power. Anyone knows how long can the EWS hold memory (of the key codes) without power connecting to it?
Don't know the answer to that but I think you problem is here. I would think that it won't loose the memory, the DME doesn't and most control units don't. If you power up the system and everything isn't hook up then there would be a problem. The key communicates with the T/R module, which tells the EWS module the right or wrong key is in the ignition. If it's the right key the EWS lets the starter relay operate and tells the DME to turn on the fuel pump and fire up the plugs. Lots of stuff going on when you insert the key.

If you want PM me your fax number and I'll send you an article from my WDS (Wiring Diagram System) program. Do you or your mechanic have BMW TIS? There is a few troubleshooter guides in there for the EWS system.

Unfortunately most roads lead to the BMW DIS machine. I hope not for you.

Joe
 

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Discussion Starter · #14 ·
Re: Help from gurus?

hudson said:
If you want PM me your fax number and I'll send you an article from my WDS (Wiring Diagram System) program. Do you or your mechanic have BMW TIS? There is a few troubleshooter guides in there for the EWS system.

Unfortunately most roads lead to the BMW DIS machine. I hope not for you.

Joe
Hi Joe, thanks for the offer. Very nice of you to take the time. I gave my Bentley's two volume E39 books to my mechanic. Volume 2 is all electricals, and they are making good use of it. I do have TIS/EPC CDs, and will re-install and get the instructions. Pain in the rear to deal with all the hardcoded data file paths especially I got five different OSes installed on my laptop with hot swappable hard disks. Life doing a hi-tech startup... :rolleyes:

I just verifyed that the EWS stores key info into its EPROM, so no memory loss their.

One of the third-party BMW specialist here in the bay area actually bought a $20K GT1, and is willing to bring the machine over to my mechanic shop next week if we are still struggling with it. So that's good. whew!
 

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Re: Help from gurus?

SandBeast said:
One of the third-party BMW specialist here in the bay area actually bought a $20K GT1, and is willing to bring the machine over to my mechanic shop next week if we are still struggling with it. So that's good. whew!
Yes that is good news. I had the opportunity to buy a used GT1 off a guy in New York who was going out business for $10K and passed it up. Sometimes I wish I hadn't.

Good luck, let us know how it turns out.
Joe
 

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Discussion Starter · #16 ·
Re: Help from gurus?

hudson said:
Wow man you got your hands full. A few questions.

Does the engine crank and not start or does it not crank at all?
Is the clutch pedal safety switch included in the main harness? Maybe out of adjustment.

Joe
Hi Joe,

The above suggestion was exactly the problem! The replacement harness ordered from the dealer not only had extra plugs, but also had missing wires and plugs - for the EWS! Argh! The mechanics traced the entire harness new and old. While matching the original, they did find the original has an extra wire from EWS plug to another connector than to the clutch. The new harness didn't have. :mad:

So after using the old wires and connectors for that, the car starts! :1:

Thanks for the help!
 

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Re: Help from gurus?

That's great news,

Sometimes it's the simple things that get you. Your mechanics did a great job hunting down the source of the problem. It's the most frustrating and humbling part of a big job such as yours, but when you find the problem you feel like King Kong. <!--[if gte vml 1]><v:shapetype id="_x0000_t75" coordsize="21600,21600" o:spt="75" o:preferrelative="t" path="[email protected]@[email protected]@[email protected]@[email protected]@5xe" filled="f" stroked="f"> <v:stroke joinstyle="miter"/> <v:formulas> <v:f eqn="if lineDrawn pixelLineWidth 0"/> <v:f eqn="sum @0 1 0"/> <v:f eqn="sum 0 0 @1"/> <v:f eqn="prod @2 1 2"/> <v:f eqn="prod @3 21600 pixelWidth"/> <v:f eqn="prod @3 21600 pixelHeight"/> <v:f eqn="sum @0 0 1"/> <v:f eqn="prod @6 1 2"/> <v:f eqn="prod @7 21600 pixelWidth"/> <v:f eqn="sum @8 21600 0"/> <v:f eqn="prod @7 21600 pixelHeight"/> <v:f eqn="sum @10 21600 0"/> </v:formulas> <v:path o:extrusionok="f" gradientshapeok="t" o:connecttype="rect"/> <o:lock v:ext="edit" aspectratio="t"/> </v:shapetype><v:shape id="_x0000_i1025" type="#_x0000_t75" alt="" style='width:11.25pt; height:11.25pt'> <v:imagedata src="file:///C:/DOCUME~1/JMS/LOCALS~1/Temp/msoclip1/01/clip_image001.gif" o:href="http://www.m5board.com/ubb/cool.gif"/> </v:shape><![endif]--><!--[if !vml]-->:cool:<!--[endif]-->

Good luck
Joe
 
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