Headlight start right when the ACC switch is on

[grave77]

Hi everyone on board, it's my first post since ages.
i went on a month vacation and when I came back to drive my car it started some strange behaviour when engine is idle, after the engine is at op. ttemperature it dips as if it's gonna switch off then runs normal again.then runs smooth but emission is bad as I can see black smoke. Associated with this is strange dip been headlights the either turn on then off when I crank engine or they stay on and then my dashboard lights are always off and turning signals wouldn't work. When am driving sometimes the dash lights are back and I get a message in German "wasserwesen fullen"

Engine runs alright but I feel sometimes something dragging it back while cruising at 60 miles/ h with rumble sound it's so minor that u feel that the road is a bit rough.
any idea where do I need to look into? I feel that I got a shorted cable somewhere but I have no idea where to start

Car is e38 750iL highline Japanese specs 1998

Thanks in advance

[grave77]

Correction, its "Waschwasser Fullen" also an update on the the symtums: while driving the engine chokes as if it's changing speed then the lights flash off and on and my dashboard lights turn off. While that happens all the signal handle functions stops working including the high beam. This happens on and off while driving.

[shogun]

First of all check the battery. It may still start the engine, but too low battery voltage can cause such electronic problems.
That means, make a load test of the battery, not just checking with a voltmeter.

[grave77]

The battery is quite new, but I changed the alternator few months ago with a second hand one, might have a rough output. Is there a schematic diagram or wiring diagram available?

[shogun]

SpaghettiCoder - BMW (http://spaghetticoder.org/bmw/)

I still suggest that you make a load test for the battery, especially in hot climate countries the batteries have a very short life.
There are special designs of batteries for hot climate countries

Excessive heat and overcharging are the two main reasons for shortened battery life

A low maintenance battery is a non-sealed battery and has a lead-antimony/calcium plate formulation. Since this is a non-sealed battery, this is the best option for hot climates because it will allow you to add water when necessary. It requires little maintenance.

[grave77]

here are the latest updates,since i had no hazard lights working, signal lights, high beam and dashboard lights i have been told that its the lights control module that causes issues as such and here is a post that i found about it:

The only obvious link on a previously similar problem experienced by a board member is here (http://www.bmwland.co.uk/forums/viewtopic.php?f=6&t=123405&hilit=one+side+light+working)

There is chat over at Bimmerfest here (http://www.bimmerfest.com/forums/showthread.php?t=443518)
Their post goes on about the symptoms of a failed Light Control Module being " No turn indicators and hazard warning lights, no high beam, no headlight flasher, no fog lights, no rear fog light, no third brake light " My car shows none of the described symptoms, just the offside side-light / angel eye ?

It's obviously not a very common fault as there is little discussion regarding this fault.

so today am gonna find a unit and swap it, yesterday i removed it to check on any dry joints and soldered all the main power joints without any luck. the unit seems to be cheap less than 50$ so fingers crossed.

cheers

[shogun]

let us know how it was solved, I am interested too.

[grave77]

Well now everything is working perfectly after replacing the module as for the engine hesitance and chocking it came out to be the MAFs so I got 2 and the 4 exhaust sensors ( 2 cat. Sensors and 2 oxygen sensors ) since they won't be as good due to carbon build up, hope that helps adding info to the forum.

[grave77]

Something else to add is the the software version should be the same or the LCM will show errors on the obc screen.
Cheers

[grave77]

A nice page about repairing an LCM Here (http://tech.bentleypublishers.com/servlet/JiveServlet/download/71-26581-258917-3865/REPAIR%20OF%20LCM%20ON%20A%20E39.pdf)