Decoding M30 connections

[Jean]

My notes after looking through 91 M30 ETM. Just trying to compare some things and see if I can decode the 25 pin X20 connector,

B6230 oil level sender
T6150 ignition coil
B6231 oil pressure switch
B6233 - afm
Y6130 - icv

S6250 - throttle switch with no egs
S6251 - throttle swithc with egs

COLORS
BL = blue
BR = brown
GE = yellow
GN = green
GR = gray
OR = orange
RS = pink
RT = red
SW = black
VI = violet
WS = white
TR = transparent

Inside the M30 ecu/relay box on the passenger side of the car:
A70 - abs/asc unit
A6004 - EML
K6300 - dme relay
K6301 - fuel pump relay
X1197 - 8 pin connector white
X6003 - 8 pin connector black
X6506 - 4 pin connector black
M6506 E-Box Fan
X6400 = B+ joint
B6235 = temp switch


B6202 engine speed reference sensor (front of the crank), on the engine harness it's the plug closest to the wirewall
B6201 cylinder identification (at spark plug wire), on the engine harness it's the plug closest to the front of the car

From top to bottom on the t-stat housing
B6232 -coolant temp
B6234 - water temp (for EML)
B6236 - coolant temp

Y6230 - 3 pin connector for oil level sensor
Y6120 - eval purge valve near the oil dipstick

By the starter
X6508 - 3 pin connector black
X6200 - 4 pin connector black for o2 sensor

E Box fan is 3 wires 1,2,3 called X6506 in ETM, pin 3 goes to X20 it's BR/GN
Also connect to X6231 oil pressure switch for some reason?

Transmission gear shift selector
X8505 7 wires
1 rt
5 or
6 gn
7 bl
4 br
3 ws
8 vi


X1171 - abs/asc control unit
X511 - for EGS used/not used

evap valve is RT/WS, BR wires
aux fan for DME is SW/GR


Fuel injector wiring 1,3,5 is BR/WS
2,4,6 is BR/GE
Switched by the ECU, common ground.
Cylinder 1 is at the front of the car.


X20

25 - bl alternator
14 - sw/gn - starter wire
18 - sw/ge to diag connector 11
24 - ws/sw from EGS
21 - gn ignition switch power
5 - sw/gr aux fan
6 - vi/gr int. climate reg.
10 - br/sw instr. cluster check control
13 - gn/vi fuel pump relay
9 - not used
14 - sw/ws inst. cluster check control / vehicle speed?
20 - sw instr cluster engine speed
8 - gr instr cluster engine speed

That's all I got so far, it's a little hard to follow ETM as it's split into 100s of pages.....

Interesting that the same connections in 89 535 ETM are different...

[drift]

^ Great Info.

[Jean]

25 pin C101.





Going to look through the rest of the ETM today to sort out the wires...

[Jean]

Here is the rest of it:

oil level sensor in the oil pan is B6230
icv is y6130
afm is b6233
oil pressure switch is b6231
spark plug id wire is b6201 (closer to front on the connector)
crank sensor is b6202 (closer to firewall)
top coolant temp sensor is b6232
middle coolant temp sensor for eml is b6234
lower coolant temp sensor is b6236
evap purge valve is y6120
connector on the passenger side of m30 under manifold x6230 3 pin
also 4 pin connector is x6200
and another 3 pin is x6508

LH Rear of Engine X69 25pins SW?
D100 x6002 is diag port
X20 connector is 25 pins SW

throttle switch pin 1 is BR/BL (goes to pin 52 of dme), pin 3 is BR/SW (goes to pin 53 of dme)and pin 2 is BR/OR (goes to ground) on non eml.
on eml additional pin 4 connects to pin 2, pin 6 connects to pin 1 and pin 5 connects to 3

coolant temp sensor pin 1 is br/rt goes to pin 45 of DME
coolant temp sensor pin 2 is br/or goes to ground

idle speed actuator pin 2 is rt/ws, pin 3 (goes to pin 4 of dme) is ws/ge and pin 1 is ws/gn (goes to pin 22 of dme)
AFM meter wires are
1 is gr/vi goes to pin 44 of dme (intake temp)
4 is gr/bl goes to pin 26 of dme (common connector)
2 is gr/ge goes to pin 7 of dme (partial load) (wiper of the pot)
3 is gr/ws goes to pin 12 of dme (full load)

starter has the following connectors
50 - goes to starter relay and jumper plug (also to pin 11 of d100)
31 is ground
30h goes to pin 15 of x20
30 RT color goes to alternator B+ and to battery B+


X69 - EML/ABS connector


X20 PINS -

13 GN/VI Fuel Pump
22 GN/WS hot in run and start (e-box fan and d100 pin 16)
17 WS/VI goes to pin 20 of D100 as TXD diag link (pin 55 of DME)
16 WS/GE goes to pin 15 of D100 as RXD diag link (pin 13 of DME)
9 BR/VI goes to pin 18 of D100 as diag link (connects to instrument cluster, and pin of DME)
12 BR/VI - instrument cluster, a/c comp unit, b6232 temp sensor on M5
19 WS/GN - instrument cluster (pin 7 of D100
18 SW/GE - starter wire or jumper plug (pin 11 of D100)
25 BL - goes to pin 12 of D100 and is alternator D+ wire
21 GN - goes to ignition coil 15 and to pin 27 of DME from ignition switch (hot on run&start)
3 - RT or RT/WS - goes to pin 2 of DME Relay for ABS
6 VI/GR - integrated climate regulation (goes to pin 41 of DME SW/BL)
5 SW/GR - goes to auxiliary fan (goes to pin 40 of dme SW/GR)
10 BR/SW - goes to instrument cluster (check panel) and to pin 42 of DME BR/SW
3 RT/WS or RT - on EML cars goes to ABS
13 - GN/VI - goes from the fuel pump relay pin 2 (pin 4 of relay goes to pin 3 of dme br/gn) to fuel pump itself through a fuse
9 - GN/BL not used (goes to pin 18 of D100) goes to pin 39 of DME
7 SW/VI - goes to pin 38 of DME and to ABS/ASC and to OnBoard Computer
24 WS/SW - goes to pin 32 of DME and to Instrument Cluster Check Control and to On Board Computer and to EGS (electronic trans control)
14 SW/WS - goes to pin 29 of DME and to instrument cluster check control and to vehicle speed output X502 connector pin 16 or 18
8 GR - goes to instrument cluster and to pin 15 of DME
20 SW - goes to instrument cluster (engine speed input) and to pin 6 of DME
15 SW/GN - from starter 30h to X276 junction for integrated climate reg, diag module of srs and on board comp and general module
5 SW/GR - ON EML CAR - SW/GR integrated climate regulation and pin 33 of EML DME
10 BR/SW - ON EML CAR - pin 42 of DME , instrument cluster/check control, automatic tranny range switch ON pin, and pin 18 of EML unit.
20 SW - on EML CAR - goes to pin 8 of DME and to instrument cluster, and to EML unit pin 29 and to EGS unit pin 21
14 SW/WS - ON EML CAR - goes to pin 3 of EML Unit, and to instrument cluster check control and instrument cluster vehicle speed output
23 - BR/GN goes to E-Box FAN pin 3 on X6506 and to pin 6 of instrument cluster and to pin 1 of Oil Pressure sWitch? B6231
24 - WS/SW - (electronic tran EGS 4HP-22) goes to pin 32 of DME and goes to EGS control unit pin 11, and to on board comp, and to Instrument cluster (standard version).
24 WS/SW - (electronic tran EGS A4S 310R) goes to pin 17 of DME, goes to on board comp, and to pin 9 of EGS Unit
5 - SW/GR (egs a4s 310r) goes to auxiliary fan and to DME A6000 pin 85 and to b9508 pressure switch for integrated climate regulation II control unit
3 - RT/WS (non eml) and RT same pin on M5 , goes to ABS unit pin 1 and to pin 2 of ABS K6300 relay
12 - GR - goes to the check engine light in cluster from a6000 dme pin 15
24 - BR/GN - oil light in the cluster from the oil pressure switch pin 1
11 - BR/GR - coolant temp sensor pin 2 (for the cluster temp gauge)
12 - BR/VI - coolant temp sensor pin 1 (for the cluster temp gauge)
20 - SW (Tach for the cluster) from pin 6 of DME
14 - SW/WS on one end speed signal for instrument cluster/check control and (SW/WS with EML or BR/RT w/o eML) on other end.
19 - WS/GN - goes to pin 7 of DME and it comes instrument cluster pin 16
10 - BR/SW goes to pin 42 of 535i x6000 dme for instrument cluster/check control of gear selector
1 BL /WS - oil level sensor B6230 (1kOhm range) for cluster / check control)
2 BL/GE - oil level sensor B6230 (1KOhm range) for cluster / check control)




d100 - diagnostics connector

[drift]

Just trying to find out why...
pin #4 of C101 of m30b35 ( 20 pin) lined up & straight forward to pin #4 C101 of '87 eta ( 20 pin), BUT...Temperature Gauge still NOT working.
What's the culprit?

[Jean]

Keep this thread 25 pin related ;)

What temp gauge sensor did you use? I know that the non EML b35 head uses two temp sensors, but I haven't looked at them closely to compare the Ohms on both. I wonder if it's important to make sure that the 2 ends from the harness have a specific order in terms of what sensors they connect to.

You can remove the end from the temp sensor, replace with a variable resistor and see if the temp gauge in cluster moves (this is how i tested my cluster) or you can short it / open circuit it and the gauge should go from 0 to max.

[Jean]

Ok so here are the important ones. It sure is nice if you are dealing with late model c101, it's got the check engine, tach and mpg wires in it vs. early cars.

x20 pin / function

25 d+
23 oil pressure light for cluster (also connects to e-box fan temp switch/motor)
24 (black/white) fuel consumption goes to on board computer plug x501 (not finding X501 in ETM wtfbbq) color ws/sw and instrument cluster/check control via x226 (and to egs unit)
22 - thick green/white
21 - ignition
20 (black) - tach engine speed input from dme pin 6 to instrument cluster engine speed input plug (color SW, goes to yellow 26 pin cluster plug X16 ) (also see x20 pin # 8 ) (also from EGS unit)
19 - si reset (goes to pin 7 on d100)
15 - starter 30h
13 - fuel pump
12 & 11 - coolant temp wires (one goes to ground, so really all you need is BR/VI if you use a single pole temp sensor).
8 (Gray) - check engine light - engine speed input from pin 15 of dme to cluster (color GR, goes to cluster plug X502 (26pin white connector) pin 3) (also see x20 pin #20)
1 & 2 - oil level sensor wires

----------
18 - starter jump wire (goes to pin 11 on d100)
17 & 16 - rxd/txd diag link goes to d100
14 - vehicle speed output (color SW/WS, goes from dme pin 29) to instrument cluster plug X502 (26pin white connector) pin 18 (also from EML unit and check control) - possibly for speed sensitive radio volume control.
10 - from pin 42 of dme to cluster (ok dme pin 42 is for automatic tranny range switch / eml tbody bs) not used w/o EGS.
4 - From what I gather it's only used on M70 cars, and hvac stuff on m50/m5 cars.