SI lights stay on after engine is started...

[kbert777]

I realize this an E30 question, but the instrument cluster and dash wiring is almost identical to the E24/28 wiring and it's much easier to get a competent answer out of this board...

After selling my '88 325iS with Automatic transmission, I have been looking for another cheap E30 to bounce around town.
I ended up with a $100 '84 318i with manual transmission. A shop rebuilt the engine 4 years ago and had problems getting the car to run. The owner finally took the car out of the shop and parked it at home.

So, after tearing into the engine and checking the basics, it turns out that the chain was two teeth of on the cam gear and the main fuel pump was very weak. Drained the oil and gas, changed fuel pump and filter, timed the engine right, cleaned the injectors real quick and she started right up. Needless to say, the quality of independent BMW shops in Las Vegas is miserable...

Here is the question...
The SI batteries were dead, not leaking, but would not charge. The green, yellow and red LED's would not come on, just the Service light. I removed the batteries and soldered some extension wires to the board and placed some freshly charged NI-CAD's in an external battery box. Turned the key on, all green LED's and the Service light came on. Jumped 7 and 1 in the 15 pin connector for 12 seconds and the Service light went out, the green LED's are all on.
Usually the LED's go off when the engine is started, but they are staying on, no matter how often you start the engine or how long it runs. Any ideas what would cause this???
The car has no OBC, an all the other SI boards I have laying around are from newer cars with OBC and Lithium batteries. How interchangeable are these boards???

Thanks in advance,

Klaus

[HayekFan]

IIRC there are two time intervals for holding the short on the connector when resetting. There's a shorter interval that resets only one of the two sets of lights (either the Green/Yellow/Reds or the Service, I can't remember which), then a longer interval that resets them both. Is it possible you only held the short for the shorter interval and maybe only reset the Service light?

[HayekFan]

Nevermind. 12 seconds is the longer interval and should have gotten them both.

http://www.unofficialbmw.com/repair_faqs/sil.html

[wokke]

the short interval is for the LEDS while the longer one is for service. AFAIK the LEDs are NOT turned off if you connect for the long period. You need to do it in two steps. I haven't done it for quite some time on any of my cars.

I had the same issue on my E34-540i. Just could'nt reset the damned LEDs with this above mentioned method. A friend of mine having a more advanced diagnosis computer did it w/o any problems. No idea WTF the problem was but LEDs are off.
You may want to try that as well Klaus.

[kbert777]

Ok, I think I have it sorted out.
Keep in mind that the problem was not reset related. After the battery change, the SI board would reset properly, oil in 3 seconds, service in 12 seconds.
I removed the cluster again to check a problem with the alternator indicator bulb, re-checked the solder points and connectors, re-installed, still the same problem.
I have been removing the negative battery cable overnight, the PO left quiet a wiring mess, about 50-60 wire nuts and 2 rolls of electrical tape, I finally removed the extra wiring and fixed the splices from an old alarm system.
Now, if the engine starts within a few seconds of cranking, the SI LED's will go out, they will still stay on when I crank longer (the cold start injector does not work (yet), the injectors are also relatively plugged, still need to get them out and run them through the cleaner).

Klaus