Folks,

I have been resurrecting my '84 190D 2.2, manual, 5 speed.....it's now tagged, inspected, & insured......am still trying to find out why the tach does not work......behind the battery is a socket.....empty when I got the car.....socket has 12 holes, in which there appears to be 9 connector sleeves......I don't know for sure what is supposed to be there.....but I think there is supposed to be an EGR Module.....the only reference to this (that I have found so far) is on Page 110 of the electrical schematics "Exhaust Gas Recirculation (Calif. Only with Manual Transmission) MY 1984 190D 2.2".....according to the schematic item N37 EGR Control Unit would have 6 used pins......but the Tachometer signal passes thru this item.....

Someone here should know what is supposed to be plugged in there?? and the part # if the proper EGR Module.....??

Someone here might know what I should jump to get the tachometer working....if possible....??

It also looks like this unit might also be necessary to resurrect the AC when I get to that point......

But the car runs sweetly, and I am getting about 40 MPG.....so I am happy without the tachometer....but it would be nice to fix it.....

Thanx,
SB

__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG

I have an '84 2.2 auto. If you post a picture of the plug, I can see what is plugged into mine if you think that will help.

Thanks, Matt

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1987 190E Garage find... 47,800 miles, more everyday!

I believe that in your car's model year 1984, EGR is turned on and off depending on engine speed. The tach signal goes through the EGR module first, then to the tachometer. No EGR, no tach.

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

I just looked this up last week as I was troubleshooting an intermittent tachometer on my '84 190D-2.2 5-speed.

The tach signal comes from the A/C compressor control module. You don't need EGR to have a tach (but you do need the A/C compressor control module for the tach to work). My car came from the factory without EGR, so there is no EGR module. Unless your car is a california model, you won't have one either.

See page 118 of 290 in the Electrical Troubleshooting Manual (PDF copy). This page is marked 127. It shows the tach signal coming from a triangle marked 'B'.

Then, see page 264 of 290 (marked 309). It shows the "Engine RPM Output" coming from the A/C compressor control unit and going to a triangle marked 'B' (which refers back to the first drawing I mentioned).

The EGR module shown in the electrical drawings can be misleading since it may not actually be present in your car.

I can send you these PDFs if you don't have the manual I'm referring to.

The A/C compressor control module is located behind the battery (there should be a plastic barrier between the battery and the module). It plugs into a socket similar to what you have described and has ~9 wires going into it.

Attached Thumbnails

   

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1989 250TD Wagon 5-speed, 160,000mi ::: Dark gray metallic / black cloth
1984 190D-2.2 5-speed, 287,000mi ::: Silver-blue metallic / black MB-tex ::: SOLD

See if you have one of these.
It's described as the A/C compressor and kick down cut-off.

(The give away is the second line on the "Rear" view Picture,
"D-Clima Kickdown".)

Assuming Cornblatt is correct, lack of this control unit /relay might explain
BOTH Tachometer and No A/C!

AND as we all know,due to Mercedes using "One Part for All" the pins used
by your car may not be all the pins on the relay.

Fastlane.

Hoowee! The price may be why it's left out.

Attached Thumbnails

     

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'84 300SD sold
124.128

Folks,

I have an '85 190E Automatic.....and both relays that were plugged into that car.......there was nothing plugged into this car.......

One relay....the rear one on the "E" has an obliterated label....
part # 001 545 8505 (not too sure about the last digit)....
obliterated line of print
5Wky 25B (not very sure of this) 12V
8 pins

The other relay from the "E"
001 5*5 78 05 * denoted unreadable character, most likely a 4
4Zyl.KVS Kickdown
05 8956 10 12V
9 pins

is the second module the same as the one used on the Diesel cars??

Thanx,
SB

I think that this is a Federal car......

__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG

I've attached a picture of what is in my car...

Attached Thumbnails

 

__________________

1989 250TD Wagon 5-speed, 160,000mi ::: Dark gray metallic / black cloth
1984 190D-2.2 5-speed, 287,000mi ::: Silver-blue metallic / black MB-tex ::: SOLD

Guys,

My module does not fit, due to the position of the locating pin......so now all I need to do is locate which pin socket is #2 and which socket is #3.......will report back later......

SB

__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG

location of the "Pin Out" charts that you got the info for the comparison,Please!

__________________
'84 300SD sold
124.128

Guys,

I got my Tachometer working by jumping ........


Car's Firewall
--------------------------
O X O O O O
X O O O O O
------------------
Radiator Tank

.......the sockets indicated by X

Thanx for all of the input......great info, Cornblatt.....you had to look that up yourself.......Thanx again!!

SB

I intend to work on the AC sometime in the future, will worry abut the rest of this circuit at that time.......

__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG