(1990) 750iL m70 no start

**Sgreen843** · 09-22-2017, 10:03 PM

Heyy hows it goin. I have an e32 that I recently bought and won't start. The engine has been rebuilt and new parts were added also. I only had it running twice. 1. Got it jump started. 2. Charged the battery then started it. So I went and bought a new battery thinking that was the issue but it wasn't. Went to attach the cables to start up wouldn't crank. I had to go to work so i Left the battery connected. Also I didn't have any interior/dome or running tail lights after the new battery.

Come back from work to go attempt to start, 1 try wants to start but cant 2 try to start and just get a click or clicks 3.the odometer and obc reading dash cut out then come back on after releasing the key. I'm lil bit lost now because now I'm thinking I'm looking for a parasitic drain somewhere. Another thing I noticed was the battery light didn't light upon turning the key.Any help is greatly appreciated.

Ive also changed the disable link in the positive cable.

**unity** · 09-22-2017, 10:13 PM

What is the battery voltage now?

If you are getting no battery warning light to come on, that could mean a burnt out warning light or a bad charging circuit wire. There is a small blue wire that runs from the alternator for the light that connects near the + post in the engine bay. This wire along with the actual positive lead run in a metal tube along the driver side intake. If the engine has been rebuilt this tube would have been handled and moved a lot. The cabling inside should have been replaced as it can crack from age and short against the metal tube. And as for the blue wire, if there is no lamp or the wire is damaged too then the alternator will not properly excite and produce voltage to charge the battery.

**shogun** · 09-22-2017, 11:29 PM

Did you also check the hidden fuse under the rear seat which is for OBC and drive away protection? http://www.bimmerboard.com/forums/posts/236235/
when you lift the driver side rear seat, you can see it.
As unity said, battery light must be on, this plug has 3 wires http://bmwe32.masscom.net/sean750/sp...gConnector.jpg
1 x for the exciter function between alternator and cluster
the other 2 are for the engine oil level sensor

**Sgreen843** · 10-06-2017, 07:04 PM

I checked the fuse under the seat and it was fine. Here's a pic of the wires from my engine. IMG_20171006_183626.jpg. What part should I be looking that's been handled a lot?

**unity** · 10-06-2017, 07:07 PM

Wow... those wires are molested badly....

**SergeBMW** · 10-06-2017, 07:59 PM

Das ist nicht gut....

There should be a third wire coming out of that connector. Is that the broken one? Also, how many cranking amps is your battery? My car would not even attempt a crank with my other spare batteries that where less than 1000 CCA. My current battery is 1200 CCA

**shogun** · 10-06-2017, 09:22 PM

On that plug there are 3 wires
2 for the engine oil level and the third one from alternator to the cluster = exciter cable. If that is not connected, the alternator will not start producing volts.
Here you can see where which wire goes in the plug http://twrite.org/shogunnew/fixes/electricalpower.html
blue-pink-brown, see the plug design
if I remember correct, the blue wire is for the alternator exciter cable, reconfirm in the ETM for your built year here http://shark.armchair.mb.ca/~dave/BMW/e32/

**Sgreen843** · 10-07-2017, 08:02 AM

The pink/blue-broown wire is broken. I bought a brand new t8 Duracell battery wit a CCA if 800.

**unity** · 10-07-2017, 09:36 AM

Blue is indeed exciter. But in that photo, they all appear damaged. I would pull off that rubber boot and investigate further.

**Sgreen843** · 10-07-2017, 04:53 PM

[ATTACH=CONFIG]612147[/ATTACIMG_20171007_164735.jpgH] this is what I found after removing the rubber. The blue excitoe wire broke off in the process from its main connection.

**unity** · 10-07-2017, 05:18 PM

Wow, someone really messed with the wiring. I would replace as much as possible as far back as possible.

**Sgreen843** · 10-07-2017, 05:18 PM

Another pic after probably removing the original tape/glue IMG_20171007_171405.jpg IMG_20171007_171405.jpg

**unity** · 10-07-2017, 05:24 PM

Yup, there is the problem. Ouch! I would guess if you get that all straightened out you will be in the clear on this issue. You may even wish to remove the connector itself and direct wire or make your own connectors.

**SergeBMW** · 10-07-2017, 05:56 PM

Here is a few links to the damaged connector, pins, and wire stress relief boot from digikey. Same MFR.

Receptacle
https://www.digikey.com/product-deta...382-ND/2054419

Pins
https://www.digikey.com/product-deta...9CT-ND/3488570

Boot
https://www.digikey.com/products/en?...ds=%09880811-2

Pins are for 17-20AWG, should be fine for the application unless the wires are less than 20. Trying to remember what their thickness was. Regardless, there are other pins for smaller wires if need be.

**Sansouci** · 10-07-2017, 06:35 PM

Serge,
How do you cross reference the BMW connectors to Digikey?
--Ken

**unity** · 10-07-2017, 06:42 PM

Ditto. I need to replace my injector connectors!

**SergeBMW** · 10-07-2017, 06:54 PM

All of those connectors have a P/N on them. The one in the photo has a P/N on there too. That should be the original MFR of all these connectors if I am not mistaken. They are made by TE Connectivity based in Switzerland. I will be replacing quite a few including this connection that is literally being held together by bare pins. You will find all the connectors on our cars by that company.

I will need to confirm this before anything! But these may be the injector connectors for our cars. My car is int he shop at the moment so I dont have access to the plugs for P/N. If anyone does, there should be a P/N on the connector.
https://www.digikey.com/product-deta...360-ND/2054525

There are slight differences in each connector on the tail end.

**shogun** · 10-07-2017, 11:08 PM

Bosch EV1, I guess these will fit, Fuel-Injector-Connector-Wiring-Plugs-Clips-Fit-EV1-OBD1-Pigtail-Cut-Splice http://www.ebay.com/itm/8-Fuel-Injec...-/231356456850

**Sgreen843** · 10-08-2017, 01:40 PM

Did some rewiring, got the battery light and interior lights, but still at a no start unfortunately.

**Sgreen843** · 10-08-2017, 03:37 PM

Multimeter reading of 11.80. It's a new battery so I'm kinda confused at this point.

**SergeBMW** · 10-08-2017, 04:21 PM

Thats a bit low for a new battery, one cell might be down quite a lot. Does the starter click at all now? Do the lights dim when you cold the key to start?

**Sgreen843** · 10-08-2017, 04:44 PM

I just checked the voltage again and now I'm at 11.6. The dash cut out completely again (with the headlights). Heard clicking after no power to crank or start. My dome light still shines bright and still have no taillights.

**Ateyourv8** · 10-08-2017, 04:48 PM

First, charge up the battery or even a jump from another car for 10 minutes should help. This sounds like it could be a bad ground somewhere in the starting/battery circuit. Here is a diagram of the starting circuit that shows where the grounds are. Make sure none are loose and check for continuity. Also check for continuity on any wires that look suspicious.
Capture.PNG

**Sgreen843** · 10-08-2017, 04:56 PM

I just checked the voltage again and now I'm at 11.6. The dash cut out completely again (with the headlights). Heard clicking after no power to crank or start. My dome light still shines bright and still have no taillights.

**unity** · 10-08-2017, 06:34 PM

Given how bad those wires are, I would very much consider bypassing the main positive lead from the alternator to the D post (that is where that three-wire connector also resides). I wonder if its grounding out inside the tube just enough to drain things can cause a no-start. Its a known issue. And even if its not the issues, its something that will have to be addressed at some point anyway. Unfortunately, there is no easy way to do it - getting to the alternator is a bit of a project.

Beyond that you could pull ALL fuses that are non vital to operation and see if the drain persists.