Outside Temp. gauge in W124?

[sub_zero]

Hi Gurus,
I wonder if anyone has passed through this, I'm thinking of retrofitting outside temp. gauge in my E220 ? is it an easy DIY? does anyone know the parts required?
Thanks
P.S: I came across a retrofit of outside temp. gauge for a W202,I think it is different.

 

[nick mercedes]

Hi Gurus,
I wonder if anyone has passed through this, I'm thinking of retrofitting outside temp. gauge in my E220 ? is it an easy DIY? does anyone know the parts required?
Thanks
P.S: I came across a retrofit of outside temp. gauge for a W202,I think it is different.

You need the loom, which are cheap enough new and a display, which aren't.

Used displays always seem to be cracked or dead for some reason.

 

[SilverSaloon]

You need the loom, which are cheap enough new and a display, which aren't.

Used displays always seem to be cracked or dead for some reason.

it may be easier to buy a complete cluster from ebay and take out the OTD unit and swap to yours. Ocassionally cheap clusters do show up, maybe with faults/damage that wont concern you as all you want is the OTD.

I suspect the same unit is used in other models aswell? W201 maybe? might be worth looking into.

thanks

derek

 

[Sp!ke]

I'm tempted to do this by canibalising a digital temperature sensor from maplins of somewhere. I recon it'd be pretty simple to fit the LCD somewhere in a OEM looking way.

http://www.tuxgraphics.org/electronics/200705/article07051.shtml

 

[219]

This is a very simple modification - all you need to do is find a donor car in a scrapyard with this option .

As said above you need the display module itself ( these differ between model ranges : W124 , W126 and W201 modules are all different and not interchangeable ) You may need the instrument pod from the donor car , I haven't done this on a W124 as both my 124's already had this option , but I have just fitted an OTG to my W126 . On the 126 , there is a piece of film blanking the hole where the display sits - it is just a matter of peeling the velvet covering from the bottom of the pod and pulling the film out to reveal the hole . The display simply slots in and fixes with two screws . On a W201 the pods are completely different and a non-OTG car does not even have the hole . I think W124 pods will be similar to W126 ones with a removable film .

As for damaged/leaking LCD displays - this only seems to be a trait of W201 ones - practically every W201 OTG I have ever seen has bleeding/damaged LCDs , but I have never seen this problem on any other model .

There is a short piece of wiring with three wires to connect : +12V feed , switched via ignition , ground , and illumination . There is also a connector with two wires which plugs into the temperature sensor . The sensor should be located behind the front numberplate where there is provision for it . I found it easiest to remove the conector from the sensor and pass the wire through a grommet in the bulkhead before resoldering the pins back on again .

The whole job took me half an hour on the W126 .

 

[grober]

there's this from Radio Spares:- http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=4086143 To big to be integrated I guess but a dab of hot glue plus some velcro

 

[Apial]

The factory fit temp display also has a connection possibly to a speed sensor. I think it has something to do with preventing false readings when the car is stationary? Might be wrong though.

 

[Dec]

My W202 doesn’t have a temperature gauge fitted as standard, I wanted something to fill the vacant window that the temperature gauge occupied so instead of a temperature gauge I opted for a volt meter from Halfords and found it much more useful as I now know, with a reasonable degree of accuracy what the condition of my battery is when the ignition key is turned to position 1, the 3 Green LEDs indicate that the alternator is charging the battery normally while the engine is running. More than 2 Red LEDs indicate that the battery is in poor condition, very useful in this cold weather.

Dec

 

[sub_zero]

Hi Pontoneer,
thanks so much for the details,I really appreciate it.
You said :
"There is a short piece of wiring with three wires to connect : +12V feed , switched via ignition , ground , and illumination ."
Where is that piece of wiring? is it attached to the display?
Where can I connect each wire? Are there certain colours?

"There is also a connector with two wires which plugs into the temperature sensor . The sensor should be located behind the front numberplate where there is provision for it . I found it easiest to remove the connector from the sensor and pass the wire through a grommet in the bulkhead before re soldering the pins back on again ."
Why didn't you start vice versa?I mean insert the two wires coming from the sensor into the bulk head and then to the OTG in the dash. I hope I got you right.

After connecting,does the OTG illuminate when you illuminate the dash? I mean will there is be light coming out of the OTG when you switch on the dash light? Also,when you change the light intensity of the dash light by the rheostat in the dash,will the light of the OTG be changed also? I mean will it be dimmed as you dimm the light of the dash? (pardon my English).
I live in Kuwait,there is a very big scrapyard here,I 'm thinking of paying them a visit and buy a cluster and get the OTG out of it.
Also I'll buy the sensor and the wires,if there is anything else just let me know.
thanks again for the explanation,you made it easier for me.
sub_zero

 

[sub_zero]

Did you all see this?

We have a member here who retrofitted OTG into his W202,but I think it is totally different than W124.Does this link of any help to me?
http://homepage.ntlworld.com/m.coxon2/tempdisplay.html
thanks

 

[SL300-24]

http://mercedesshop.com/shopforum/showthread.php?p=258099

This may help you......

http://www.mercedesshop.com/Wikka/W124InstCluster


This also......

 

[grober]

The OTG for the w202 model is a different unit altogether. there is different wiring pre and post 87 as APIAL says. You may not have any of the required wiring behind the instrument cluster if you didn't have a OTG display fitted originally. Best to place the sensor in the standard position behind the numberplate-its obvious when you remove the plate. The correct wiring is to then bring the sensor LEADS (2wires) to the inside of the fuse box where it is connected via a 2 pin plug to the wires leading thro the bulkhead to the back of the cluster. NOTE:- There won't be a 2 pin socket to connect to in the fuse box if the correct wiring loom isn't fitted. You will need this loom as well as the OTG indicator unit from the donor car or buy it from MB. This wiring diagram might help?

 

[sub_zero]

Thanks grober....
So I have to drive the 2 wires coming out of the temp. sensor to the fuse box,so OTG has a fuse inside the fusebox dedicated for it,right?
after that,there is a loom that connects the OTG fuse to to the end of the temp. display in the cluster,right?
Hope I got it right this time.

 

[grober]

What it means is that the OTG is normally powered from fuse 6 (rated at 8AMPS) in the main fuse box. There may or may not be a separate power lead from this fuse to terminal 5 of the OTG indicator unit. If you can pick up an ignition switched live 12v supply at the rear of the cluster this should be fine since the cluster is supplied by the same fuse 6. The light has to be powered via the rotary dimmer switch ( terminal 58d) to control the illumination of the unit.