from :
http://www.bmwe30.net/tech/sil_reset.htm... You'll need a piece of electrical wire (10/15 cm) to serve as a jumper wire.
According to Patrick Farrel, a BMW master tech working at a dealer in MD, you
should always use a fused jumper wire.
First, locate de diagnostic socket, at the engine compartment.
There are two different types: up to 1987, it's located near the intake
manifold, and has a red cap:
After 1987, you have to find a big round black plastic socket, with a cap held
by a plastic strap, located near the oil dipstick (M20 engines) or near the
firewall, driver's side (M40 engines):
Pull the cap (early connector), or unscrew it (late connector), and you'll see
a number of connectors, depending of the type of plug (see the diagrams below).
Go to :
http://www.bmwe30.net/tech/sil_reset.htm... for diagrams
According to the type of plug on your car, locate the right connectors, marked
red in the diagrams;
Use the jumper wire to connect them together;
Turn the key to ON position, without starting the car;
When the 5 LED's in the dash light up (3/4 seconds), turn off the key. If you
keep the ignition on, another 6/7 seconds, after the LED's appear, you'll
perform an inspection reset, too.
Disconnect the jumper wire.
Make sure you jump the right connectors! The best way to follow the diagram for
the late type connector is to match its center circle cut (that looks like a
pacman :o)) with the one in your car. The earlier one has a flat side, so it's
easier to follow.
/////////////////////////////////////////////////////////
From :
http://www.bmwe30.net/tech/sil_reset.htm...BMW Service indicator lights FAQ.
Contents:
Resetting the Service Indicator Lights.
The Dummy Plug.
Replacing the NiCad batteries. Updated 8/3/96
Also check the Electrical FAQ
The Service Indicator Lights
The BMW service indicator lights are considered by many to be totally useless
for indicating when you should service the car. The cheapest, ugliest solution
for turning off the service light is to cover them up with black tape. If you
want to be more adventurous, you can remove the instrument cluster and cut the
wire going to the lights. True motorheads will read on though.
The service indicator lights are reset through a pin in the diagnostic
connector located in the engine compartment. There are 2 types of diagnostic
connectors used on BMWs. One is a 15 pin connector used on 1987 and earlier
cars, the other is a 20 pin connector used on 1987-on cars. In what follows the
15 pin connector is referred to as the early type and the 20 pin as the late
type. Resetting the service indicator lights is described below. The most
common problem with resetting the service lights is bad NiCad batteries in the
instrument cluster. The batteries seem to fail pretty consistently after 4
years. The symptoms of this are:
1. The inspection light comes on.
2. Resetting the light according to the instructions below either doesn't work
or works for a short period of time and then the inspection light comes back
on.
The fix for this is to replace the batteries as described below.
Relevant Roundel references:
The Roundel is the monthly publication of the BMW Car Club of America BMW CCA.
Jan 1992, Nov 1991, Dec 1989, May 1988 -- Resetting the service indicator
lights
Nov 1991 -- Replacing the Nicads.
Resetting the service indicator lights.
Late type connector:
The service indicator lights are reset by connecting pin 7 to pin 19(ground).
The proper way to do this is to have the ignition off and place a jumper wire
between pins 7 and 19 (make sure you get the right pins!). Then turn the
ignition switch to position 2 (run, NOT start), when the service light goes
out, turn the ignition off. This should take a few seconds for an oil reset,
8-10 seconds for an inspection reset. All green lights should come on when the
service light goes out. The difference between resetting the oil service light
and the inspection light is in the length of time you have the jumper in place
with the ignition on. This means that if you are resetting the oil service
light, you should turn off the ignition immediately after the light goes out.
If you leave the jumper in too long with the ignition on, you will perform an
inspection reset as well and the next service indicator will come up as an oil
service rather than an inspection.
The service light reset tools that I have seen connect to 3 pins of the
diagnostic connector: pin 7,14 and 19. The connection to 14 is to power the
tool. The less sophisticated tool has only one switch that connects pin 7 to
19. While those pins are tied together a red LED blinks to measure time. You
count blinks and manually turn off the tool after the appropriate number of
counts for oil or inspection reset. The more sophisticated tool has two
switches, one for oil reset, one for inspection. It must have a built in timer
that jumps pin 7 to 19 for the correct time.
Notes on the latest model cars (93 on?):
(can someone please verify this?) It is claimed that the above procedure doesnt
quite work on the most recent model year cars. Instead of waiting for the
lights to go out, you have to disconnect the jumper between 7 and 19 while the
ignition is still on.
To reset OIL SERVICE, maintain the connection for approximately 3 seconds.
To reset INSPECTION, maintain the connection for approximately 12 seconds.
Early type connector:
The procedure is the same as above, but you jumper pin 7 (the service indicator
pin) to pin 1 (the ground pin).
The early type connector:
*** (10) ***
** (9) (11) ***
* *
* (2) *
* (8) (3) *
* *
* (7) *
* (1) *
* (4) *
* *
* (6) *
* (15) (5) *
* *
** (14) (12) ***
*** (13) ***
Diagnosis plug connections:
No. Terminal Designation
1 31 Ground
2 - -
3 - -
4 FT Temperature gauge
5 L Engin M10B18 Interfrator output for CO adjustment
Engin M30B34 Oxygen Sensor signal
6 A Diagnosis lead for SRS
7 SI Service indicator
8 P+ Position sender
9 S Shielding
10 P- Position sender
11 50 Starting pulse for starter
12 61 Alternator charge indicator
13 1 Ignition signal
14 30 battery +
15 15 Power supply for ignition
The late type connector:
** ***
*** (1) ***
** (12) (2) ***
* *
* (11) (20) (13) (3) *
* *
* (10) (19) (14) (4) *
* *
* (15) *
* (9) (18) (5) *
* (16) *
* (17) *
** (8) (6) **
** ***
*** (7) ***
From the BMW NA 1989 Electrical Troubleshooting Manual for the 325i/iS:
Pin Wire Size Wire Color Circuit and Component Connected
1 1 BK Ignition Coil, Motronic Control Unit
6 0.5 WT/BK SRS Connector (Not Used)
7 0.5 WT/GN Service Interval Indicator, Service Interval Processor(Reset).
11 2.5 BK/YL Starter, Start Signal(50)
12 0.75 BU Charge, Alternator(D+)
14 2.5 RD Battery
15 0.5 WT/YL Motronic Control Unit(RXD)
16 1.5 GN/WT Oxygen Sensor
18 0.5 GN/BU Motronic Control Unit(Programming Voltage)
19 1.5BR BR Ground Distribution(G103)
20 0.5 WT/VI Motronic Control Unit(TXD)
(return to contents)
The Dummy plug.
Late models:
The cap on the diagnostic connector is actually an electrical connector that
shorts together the following pins:
--pins 18 and 20 to pin 19.
--pin 14 to 15.
Other things you can do with the diagnostic connector.
(I've never tried any of these!!!:)
Remote Starter: Connecting a remote starter switch to pins 11 and 14 will allow
you to start the engine or "bump" it into position for valve adjusting.
Read O2 sensor: ???
Motronic faults: ???
/////////////////////////////////////////////////////////
Service Interval Indicator
Since the early 1980's and the adoption of the Bosch Motronics system, BMW has
used a very neat computer device to calculate when you should change oil and
when a Service Inspection is due. Typically, the Service Interval Indicator
(SI) is a count down integrated circuit board whose outputs are an LED (Light
Emitting Diode) display of five green, one yellow, and one (or three) red
indicators plus "OIL SERVICE" and "INSPECTION". Driving conditions are utilized
to better calculate when an oil change or check up is needed.
Each time the ignition is turned on, the SI display is activated until the
engine starts, and a clear signal extinguishes the display. If the countdown
has progressed through the green to the yellow and/or red LEDs, the clear
signal is disabled and the yellow, red and "OIL SERVICE" or "INSPECTION" LEDs
(or bulbs) remain illuminated.
There are six variable inputs to the Service Interval Processor, plus power and
ground. Each of these causes an incremental progression in the countdown (or
resetting) of the SI Display. There are two categories of countdown to obtain
an "INSPECTION" output: wear factors and time factors. Normally, there will be
two "OIL SERVICE" ...
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