Electrical Issue

[bpossel]

Hi All!

Moved topic to "Auto Transmission Wiring" ...
Thank you,
Bob
---------------------------------------

Does anyone have knowledge of the throttle switch wiring (not listed on the color schematic)?  How does this connect to the transmission?





Throttle Switch


Currently sorting out:
1. Generator light in dash does not illuminate when turn the key to 2nd position. checked bulb and it is good
2. Throttle body switch & transmission wiring ...

Thanks,
Bob  

[graphic66]

Probably low brake fluid in your master cylinder.

[bpossel]

This will really be a good test for all those knowledgeable with the 113 electric, and that's not me... :oops:

Brake fluid full!  I found that one of the horn wires was touching the bracket that holds it to the frame.

Now, when I open the door, just the middle red light (brake control light) comes on, as it should.  Generator light does not come on, as it should.

So, that all looks good!

Now the issue is that the windshield wiper motor does not work.
Also, the horns dont work....

Any add'l ideas are appreciated.  I do have the color electric schematic, but I am not a "EE".

Thanks!
Bob

[Garry]

Hi Bob,
I have had a similar electrical problem to you.
WAfter the paint job and re fitting of the engine and all the wiring, open the door and the generator light came on and the fuel pump started to go.  The brake warning light stayed on all the time.

I pulled one of the fuses initially that stopped the fuel pump going (only when the doors opened)and the generator light, and then started the process of trying to tract where the problem was with out luck. I then had an auto elect look at it and after four hours of no find, stopped him. and that is where I am at the moment.  However, what he did say for my four hours worth is that he was looking for an incorrectly earthed lead.  What unfortunately he did not look at and where I probably should have started was at the ignition switch.  One day I will have another go when I am satisfied that I have found a good elect guy, meanwhile one brake light in the dash when I drive.

Good luck

[al_lieffring]

The ignition coming on when the door is opened is a wiring defect in the original factory design. The brake warning light will feed back through the ignition switch when the brake fluid is low and the door is opened.

Even with the fluid resivior full it is very common for one or both of the float switches under the lids of the resivior to sink and cause this feed back. Remove the two (white?) plastic lids and see if the copper discs rises up clear of the electrical contacts. I do not know if the float switches are still available seperate from the tank, but many (25) years ago the complete tank assembly cost less than the two switches bought seperately.

The horn and wipers are on the same fuse, it could have burnt out from the horn wire contacting the mounting bracket.

Al

[bpossel]

Thanks Guys!

I just checked the floats, and they do pop up nicely when remove the lids...

Here is the current issue:
1.  Horns dont work
2.  Wipers dont work (they did work a couple of days ago when I tested them)
3.  Washer pump does not work
4.  Fuse #2 is good, replaced with new one...
5.  Fuse #4 is removed.  Dont want to run fuel pump while testing electric.

All else seems to work great!

The common points to the above issue is fuse #2, which is good and also the fact that all of these items run thru the turn signal stalk.

Tomorrow I will remove the stalk and make sure all is connected right.

Any other ideas?

Thanks again!
Bob

[scoot]

quote:Originally posted by bpossel


When I open the drivers door, the fuel gage moves up a bit (have installed only 4 gallons of gas) and the low fuel indicated light in the dash comes on.  I can flip the turn signal lever up or down and the left & right signal lights come on respectfully..

When I hit the horn, it sounds off, but faintly....

I dont recall that the horn, signal lights and fuel gage working without turning the ignition key on?  Do I have a short?

The faint horn I would attribute to a bad ground possibly.  I don't think that the signal lights or the fuel should work without the ignition on, not sure about the horn.  Regarding the wipers, even though they worked before I would test for power at the wiper plug when the wipers are turned on just to make sure.  Or possibly the wiper relay...   I thought the answers from others regarding the low fuel light and other things happening when you open the door were interesting - I would have had no idea.   good luck!  Scott

[Garry]

Al,
I also just checked my floats as you had suggested to Bob and yep, one did not raise up.  The float was off to the side, when I put it back under the float switch it then worked and the light went out. As a bonus, so did my petrol pump working when I open the door problem go away.  I think I have found my grounding problem, in the Brake resevior when the float drops down it must be earthing. I suspect that is a wiring problem further back in the brake electrical warning system that somehow feeds power to the petrol pump when the door is opened!!! but only when the brake float switch is turned on. At least I can direct the motor elect to that area now.

One problem solved, one to go for me.

[hauser]

Bob, since the car was completely painted there should be some ares that would require paint removal in order to get proper ground?

[bpossel]

Thanks Hauser!

Actually, after the car was stripped to the metal and just before they started to paint, I put round stickers on all of the grounding points.  After the car was painted, I simply removed all the round stickers and lightly sanded those areas.  I did all of this to avoid these mystery electrical issues.  I guess its all part of a resto.  More work on this will continue today.  I also hope to start 'er up today!  
Bob

quote:Originally posted by hauser

Bob, since the car was completely painted there should be some ares that would require paint removal in order to get proper ground?

[bpossel]

Hi Garry,

As Al mentioned below, what you experienced is "normal" for our cars.  This was a defect, of sorts, with our wiring, and is normal. Sounds like you got your issue fixed.  I wouldnt do anything else on your electric if the float was was your issue.  Just drive and enjoy!
Bob

quote:Originally posted by Garry

Al,
I also just checked my floats as you had suggested to Bob and yep, one did not raise up.  The float was off to the side, when I put it back under the float switch it then worked and the light went out. As a bonus, so did my petrol pump working when I open the door problem go away.  I think I have found my grounding problem, in the Brake resevior when the float drops down it must be earthing. I suspect that is a wiring problem further back in the brake electrical warning system that somehow feeds power to the petrol pump when the door is opened!!! but only when the brake float switch is turned on. At least I can direct the motor elect to that area now.

One problem solved, one to go for me.

[Garry]

I wish,  Its ok so long as the float does not sink again, however, there is still an earthing problem there when that does happen that should not do so.

Must say your car is looking absolutely fantastic and the photos that you have been taking during the process have been for me and I am sure others, invaluable for reference. Are you taking it to Blacklick next year? I am planning to be there.

Garry

[bpossel]

Thanks Garry!
That's great that you will be at Joe's next year!  I will also be there and with Pagoda.  Should be broken in by then... i hope!
Bob

quote:Originally posted by Garry

I wish,  Its ok so long as the float does not sink again, however, there is still an earthing problem there when that does happen that should not do so.

Must say your car is looking absolutely fantastic and the photos that you have been taking during the process have been for me and I am sure others, invaluable for reference. Are you taking it to Blacklick next year? I am planning to be there.

Garry

[Naj ✝︎]

quote:Originally posted by bpossel

I have not yet started up my car, but am getting close....

6.  Generator light in dash does not illuminate when turn the key to 2nd position.  Shouldnt this be lit and then go out once the car is started and running?  

All else seems to work great!

Any advice, direction, other ideas... is appreciated!

Thanks,
Bob

Check the 3 wire plug on the voltage regulator for corossion etc. and connections on the alternator.

naj

[hands_aus]

The door ajar, brake float problem is 'known'. A solution was posted.
A search should find a topic

look at this

What's the Deal on the Brake Warning/ Door Ajar Light?
By Ola Kristofersson
When you open the door on a 113-model car, the red brake warning light comes on. This is to signify that the electrical brake warning system is working OK. So why is the red brake light associated with opening the door? Legislation demanded brake fluid low and door ajar warnings. There was only one light position left on the kombi instrument, so they decided to use the same light for both functions.
First, a description of this W113 feature:
All Mercedes cars are designed so that when the key is switched to "on", the wiring section No 54 in electrical system is in use. Section No 30 is straight from 12V+ on battery. A primary rule is that section No 30 and No 54 are never to be connected, as this bypasses the ignition key and empties the battery.
The 113 is designed so that:
The courtesy light below the dash is connected to No 30. Light is (may be) lit as door is opened. Brake fluid warning is connected to 54 (Light is on when car is running and level is low). Now, the M-B designers wanted to find a way to check that the warning light bulb was OK. And, they did that by using the courtesy light door switch. This also resulted in a "door ajar" warning function. This design carries with it an unfortunate effect: If the brake fluid level is low, and the door is opened, 30 and 54 will be connected. Means ignition will go on, and the fuel feed pump will start up. Fuel can be squirted around if one is performing work on the fuel system in the car. A wise thing to do is to disconnect the battery before starting any maintenance work on the fuel system.
Now, a remedy:
By simply fitting a diode in the circuit between the fluid level sender and this red light bulb in the combi instrument. A Si diode, 1A with the (+) side facing the bulb will do fine, and it may be easily hidden in the wiring harness of the car.

[glennard]

Bob, Been asking how this is wired and how it's 'sposed' to work-    CSS, throttle s/w, tranny s/ws, tranny solenoids, kickdown, etc.  This is all tied together on auto trannies ---???  If one thing is off, trouble??