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Re: Two big weekend issues...

My 88 535is had the same starting issue. it could be the ECU. Try turning the ignition with your left hand and open the glove box with your right hand. Tap the ECU box and the car should fire right up. This is a very common issue. there are 3 solder joints on a resistor pack that are natorious for cracking. i heated mine back up and have not had an issue for 3 years.

Check out this link.. good luck

http://e28-535i.com/technical/e28-ECU_Repair.php


Sergio
88 535is
Austin, TX

Take the lower cover off under the steering column

and find and test the wires to the ignition switch. Big red is power in, always hot. Green is power out when key is in run position, should be dead when in off.

Is that where everyone is hiding?

I do need to do some more learning. I'm sure with the age of this car there are some things like this that are going to come up from time to time. For now - I guess I'm going to start pulling the relay until I can figure it out.
Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

It looks like you need to learn how to read the

ETM diagrams and do some wire tracing with your ohm/volt meter or get someone to help. I am reluctant to tell you to get a new ignition switch (just the switch part) without more testing, however you should not have power through it with the key off. I don't know if you have an auto or stick either. There are people with knowledge on other boards ( e23 board at bim merboard dot com and maybe mye28 for example) most all of the old roadfly e23/28 guys are over there now on BB. I have posted one of the pages from the ETM.
http://www.e38.org/e28/e28_88_etm.pdf

Any tips on where to go next?

This is getting into an area where I don't have a clue... ThanksMinetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

Sounds like something bad with the ignition switch

or its wiring. The main relay is staying on it seems. A relay coil will draw probably 100 to 150 ma when on.

12.29 with no key in the ignition...

Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

Wow - now I understand.. HoDeeDoh...

Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

Take out the main relay and look carefully at its

bottom. You should see 85 the power side of the relay coil, 86 the coil ground side, 30 the main power side from the battery and 87 or 87a/b the output pin. Compare the relay prongs with the socket slots and find 85 in the socket. Test it for voltage with your meter, with meter ground to 86 or the the car body. When the key is off there should be no power. Key on there should be about 12 volts. This relay supplies power to the Motronic Control and to the fuel pump relay when it is activated.

Re: I have not looked at your wiring diagram but for

OK.. Where would I find pin 86? Is it near Studio 54?
Thanks - I really don't know..
Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

I have not looked at your wiring diagram but for

my 83 the main relay only gets power to its coil by way of the ignition switch in run or in start. Pull the main relay and check pin 86 in the socket for voltage.

the strangest thing is the main relay

being pulled causes it to go from 114 to 4 mA - Should the realy be drawing that much - or is there something else in the circuit which the relay then connects?

I have the Bentley diagrams - but seeing as how I failed English and Math from the 3rd grade on - I have trouble reading them and understanding what they're trying to tell me.

I was a bad, bad student... But I can rebuild an M30...
Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

I can't imagine unless it's something in the

ignition switch. The 10 ma may be the radio memory. Have you researched the wiring diagram? See ETMs on e38.org/e28.

All the bulbs are out.

With all fuses out there was still a reading of 114 mA.
I took out the main relay and it dropped to under 10 mA.

Once again - with ALL the fuses out it was still reading 114.
Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

First, open trunk and see if trunk light is warm.

Mine was staying on all the time. Next put your ammeter between battery terminal and car and start pulling fuses. You should be less that 50 ma. My 750 is only about 30ma forgot what my e28 is. Will check.

Re: Reading with all fuses

from positive post to positive cable is 230 mA. After I pull #5 it goes to 110 - that's all I know so far..Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"

Two big weekend issues...

Mystery 1)
Start car - drive to store - turn off car - go buy candy bar - get back in car - turn key - starter just cranks and cranks and cranks... First nothing - then more cranking - then more nothing... Then more cranking - and slowly, ever so slowly (as long as you leave the starter engaged while this is going on) the car begins to sputter and cough it's way back to life... (Brand new fuel pumps (pressure and transfer)... Leave the car for more than a few minutes after you shut it off (30 minutes to an hour) turn the key - starts right away...

That would be mystery number 1.

Issue number 2 is:
Can anyone just give me a few things I can unplug or cut the power to that might be causing a battery rundown.(3-5 days and battery is weak - this is also brand new) I've already done the lights (trunk, hood, glove) I don't need any special features other than heat or the radio and wipers. I just want the car to run...

Thanks..
Minetree
88 535i
210,000+ Still Kickin
Remaned Head, all stock.
88 Mazda 323 4Banger
168,000+ Still Kickin
Terminal Velocity 113mph
32miles to the gallon
<img src="http://www.michaelminetree.com/DSCN0004.JPG"