BMW E38 tachometer signal not working on the dash

[Mr. October]

dears
I have E38 1995 730i v8 manual transmission , I mistakenly played with the harness in the DME box without isolating the battery , there was some extra wires connected to the original harness , I removed all the extra wires and didn't take a picture of it in case. doing that i head a wire contact . now the tachometer(RPM) signal is not working and the red light (!) is now lighting (not sure if it is because of the Tachometer).
anyone knows how to fix it ? does anyone have the DME wiring diagram ,or the tachometer wiring diagram from Crankshaft(signal source ?!) all the way to the cluster? btw , consumption indicator is also not working(not sure if it's related)
thanks in advance

[Mayorchuck]

Welcome here. Try digging around in here:

https://www.newtis.info/tisv2/a/en/e38-735i-lim/

Taking a quick look, I think this is the pinout for your car:

Plug connector overview

Number	X-pin, colour	Description
X6000	88-pin, natural	Plug connector DME control unit

Pin assignments at plug connector X6000

Pin	Type	Description /Signal type	Connection /Measuring notes
1	A	Signal, oxygen sensor heater	Connector, DMW oxygen sensor 1
2	A	Idle actuator closing winding	Idle actuator
3	A	Fuel injector cyl. 1	Fuel injector cyl. 1
4	A	Fuel injector cyl. 4	Fuel injector cyl. 4
5	A	Fuel injector cyl. 6	Fuel injector cyl. 6
6	M	Ground, fuel injector	Ground point
7	A	Fuel injector cyl. 7	Fuel injector cyl. 7
8	A	Defect lamp (USA only)	Instrument cluster
9	E	Start signal	Start relay
10	E	Antitheft alarm system signal (EWS)	Electronic immobilizer control unit (EWS)
11	A	A/C compressor signal	Heating and A/C control module
12	E	Signal, terminal 50	Ignition switch
13	E	Knock sensor signal	Knock sensor
14		Not used
15		Not used
16	E	Intake air temperature	Intake air temperature sensor
17	E	Ground, hot-film air mass meter	Hot-film air mass meter
18	E	Oxygen sensor signal	Heated oxygen sensor 2 in front of catalytic converter
19	E	Oxygen sensor signal	Heated oxygen sensor 1 in front of catalytic converter
20	A	Crankshaft sensor signal (speed and position)	Crankshaft sensor
21	A	Camshaft sensor signal (cylinder reference)	Hall-effect sensor, camshaft 1
22	A	Ignition signal cyl. 6	Ignition coil cyl. 6
23	A	Ignition signal cyl. 3	Ignition coil cyl. 3
24	A	Ignition signal cyl. 7	Ignition coil cyl. 7
25	A	Ignition signal cyl. 2	Ignition coil cyl. 2
26	E	Terminal 30	Fuse F109
27	A	DME relay	DME relay
28	M	Ground for electronics and sensor shield	Ground connector
29	A	Idle actuator opening winding	Idle actuator
30	E	Signal, oxygen sensor heater	Heated oxygen sensor 1 in front of catalytic converter Heated oxygen sensor 2 in front of catalytic converter
31	A	Fuel injector cyl. 5	Fuel injector cyl. 5
32	A	Fuel injector cyl. 8	Fuel injector cyl. 8
33	A	Fuel injector cyl. 3	Fuel injector cyl. 3
34	M	Ground, remaining output stages (apart from ignition and fuel injectors)	Ground point
35	A	Fuel injector cyl. 2	Fuel injector cyl. 2
36	A	Signal, A/C compressor relay	Heating and A/C control module
37		Not used
38		Not used
39		Not used
40	E	Knock sensor signal	Knock sensor
41	E	Knock sensor signal	Knock sensor
42	E	Fuel reserve signal	Instrument cluster
43		Not used
44	E	Throttle potentiometer signal	Throttle potentiometer
45	M	Signal, hot-film air mass meter	Hot-film air mass meter
46	A	Signal, oxygen sensor Ground	Oxygen sensors
47		Not used
48		Not used
49	A	Ignition signal cyl. 1	Ignition coil cyl. 1
50	A	Ignition signal cyl. 5	Ignition coil cyl. 5
51	A	Ignition signal cyl. 4	Ignition coil cyl. 4
52	A	Ignition signal cyl. 8	Ignition coil cyl. 8
53	A	Throttle potentiometer + 5 V supply	Throttle potentiometer
54	E	Terminal 87	Fuse F1
55	M	Ignition ground	Ground point
56	E	Terminal 15	Ignition switch
57		Not used
58		Not used
59	E	Signal input Characteristic map, cooling	Characteristic map, cooling
60	E	Programming voltage input	Diagnostic connector
61	E	Signal input Tank ventilation valve	Charcoal filter valve
62		Not used
63	E	EKP relay	Fuel pump relay 1
64		Not used
65		Not used
66		Not used
67		Not used
68		Not used
69	E	Air conditioning system standby signal	Heating and A/C control module
70	E	Knock sensor signal	Knock sensor
71	M	Ground for temperature sensor, throttle potentiometer and knock sensors	Ground connector
72		Not used
73		Not used
74	E	Signal, temperature sensor	Dual temperature sensor
75		Not used
76	E	Oxygen sensor signal	Heated oxygen sensor 2 behind catalytic converter
77	E	Oxygen sensor signal	Heated oxygen sensor 1 behind catalytic converter
78	E	Crankshaft sensor signal (speed and position)	Crankshaft sensor
79	E	Rear right speed signal	ABS control unit ABS/ASC control unit
80	A	TD signal (engine speed)	Connector TD signal
81		Not used
82	A	Ignition timing adjustment	Not used
83	A	Injection signal	Integrated electronic control unit (IKE)
84		Not used
85	E/A	CAN-bus low	AGS transmission control unit
86	E/A	CAN-bus high	AGS transmission control unit
87		Not used
88	E/A	Diagnostic link TXD	Diagnostic connector