Author Topic: Turn Signal Relay Buzzing? (Read 5527 times)

acbrock · « **Reply #50 on:** May 15, 2024, 12:10:38 »

ah 12 is just the Horn Ground. Ok so I will test that but I do not have horns. Noticed that about 6 months ago. I will try and trace the wire that was in 12 which is black/white which from the schematic should be the Turn Signal. If I can get that to work I wills start from there and work around the plug.

Leester · « **Reply #51 on:** May 15, 2024, 12:14:56 »

I suggest narrowing your focus.
1. Disconnect your battery
2. Restore the fuse box to its original position
3. Focus on the wires in the female connector for the multi-function switch
a. make a blank chart like the one below
b. if you havent already done so make yourself a six foot wire with alligator clips on the ends
c. clip one end of that wire to one of the end users in the chart below and bring the other end into the cabin
d. using your ohmmeter connect one lead of the ohm meter to the alligator clip and probe each wire with the other lead
e. when you have a match, wrap a piece of tape around the wire and identify that wire's end user (use same pin # and
description as the chart and enter it into your chart)
f. remove the alligator clip from that end user and clip it to a different end user and repeat.

This is essentially what BobH suggests. When you have all 12 wires and their end users identified post it here.

acbrock · « **Reply #52 on:** May 15, 2024, 16:27:15 »

I will get the fuse box all worked out and cleaned and then start this process. Thanks for all the notes!

acbrock · « **Reply #53 on:** May 15, 2024, 22:06:54 »

Oof. What a day. My knees and back are killing me. So I Put the Fuse Box back together and Put all the Female pins back in Connector so nothing is "Dangling". I then began the testing. I used a new Multimeter which I think is more accurate....

So I started testing things. I think the theory here is that if I connect to line to 1 end, say the Plug on the Wiper Relay (Assuming that is the big one near the wiper motor) Then run that line into the cockpit and connect one of the probes to the end of the line. Then with the other Probe touch all 12 female ports 1 at a time... One of them should go to 0.00 and that is the Correct Pin for that device.

If that is not correct then the rest is not correct so no need to keep reading!

. So while doing this I got readings on lots of the female pins, some low some OL but for the Relay I got 0.00 only on Pin4. I got a few different 0.00 checking all the pins on the Headlight Connector inside the headlight.

Pin1. 0.00 on Wiper Motor
Pin2.
Pin3.
Pin4. 0.00 on Wiper Relay
Pin5
Pin6. 0.00 on Drivers Side Headlight Plug in the Top Pin on the side with 3. But I got 0.00 on other pins on the connector...
Pin7. 0.00 on Wiper Washer Motor Also 0.00 on Drivers Side Headlight Plug in the Top Pin on the 3.
Pin8
Pin9 0.00 on Drivers Side Headlight plug on the Bottom Pin on the side with 2 pins.
Pin10
Pin11
Pin12. 0.00 on Drivers Side Headlight plug on the Top Pin on the side with 2 pins.

Does not seem correct?

I attached the battery to see if connector got power. First thing I noticed is that in Position 2 on the ignition I did not get any noise. The car does start but no buzzing. The Headlights worked but I think maybe I lost power to something. I am going to quit before I do something stupid. I will recheck everything later or in the morning and see if there is something I forgot to connect.

Pic is of the setting I using to get to 0.00.

Leester · « **Reply #54 on:** May 15, 2024, 22:34:22 »

I use an old analog ohm meter so BobH is going to have to weigh in on your meter readings.

The wiper motor relay is on the driver side of engine compartment (assuming a USA vehicle) and is not near the wiper motor. On the left side of the engine bay just forward of the windshield washer motor and nest to the power brake brake booster you should see 3 relays in a row. The larger of the three is the ww relay. It has a 6 pin female connector.

I guess 00 reading means no resistance (meaning full continuity). Let me take a longer look at your readings.

acbrock · « **Reply #55 on:** May 15, 2024, 22:59:10 »

Haha. So one of the wires I thought I found is wrong! So what is the big relay on the right side near the wiper motor.
I know it seems crazy but I actually get relieved when I have done it wrong! That way I can fix my process learn a little more and hopefully the car is not is as bad shape as I thought the day before.

Leester · « **Reply #56 on:** May 15, 2024, 23:00:26 »

You wrote "I think the theory here is that if I connect to line to 1 end, say the Plug on the Wiper Relay (Assuming that is the big one near the wiper motor) Then run that line into the cockpit and connect one of the probes to the end of the line. Then with the other Probe touch all 12 female ports 1 at a time... One of them should go to 0.00 and that is the Correct Pin for that device."

CORRECT. But you also need to identify the specific pin. For example, if you look back at the chart, pin 2 (of the female connector for the multi function swith - aka turn signal switch) should have continuity with the pin in the ww relay connector that goes to terminal 56 on the ww relay. So, one end of your line should attach to the correct female pin on the connector for the relay that attaches to terminal 56 on the relay. Then probe as you described above each of the 12 female pins in the multi function switch connector until you find continuity.

Leester · « **Reply #57 on:** May 15, 2024, 23:03:54 »

On my car, and I think most, the only big thing that looks like a relay is the voltage regulator. There also may be a fuse box on a bracket but thats for the radio and antenna.

acbrock · « **Reply #58 on:** May 16, 2024, 00:39:36 »

Ok cool thanks. Ah lightbulb just went off. 56 will be those numbers in the relays. Excellent. I will find that one first! One at a time I will get them!

acbrock · « **Reply #59 on:** May 16, 2024, 02:41:13 »

Ok so ran out and wanted to check this stuff out. So I have 3 relays... First is round 3 Pin, 2nd is Rectangle 5 Pins, 3rd is rectangle 4 Pins. The middle one, the middle pin is 56. So I attached it and ran the meter. One of them got really low 0.01. So I am going to check it again in the AM.

BobH · « **Reply #60 on:** May 16, 2024, 07:48:23 »

Some of these wires will be split and go to several different destinations, ie the blinker/turn signal wire will split (somewhere) and feed the front blinker, rear blinker and cluster blinker light, so you'll read 00 at various different locations. Likewise, pin 4 on the wiper motor, is fed from fuse 2, so this will be common to the wire that should terminate at pin 6 on the connector, so you are going to get some misleading readings

If you concentrate on the wires that have a single destination first, ie wire from pin 1 to the washer pump, once confirmed tick that one off. Wire from pin 2 to wiper relay pin 56, tick that one off. Should mention that all relays or connectors should be unplugged, or else you'll read through relay coils or lamp filaments and this will give a false reading

Unfortunately, because your loom colours don't match the male connector, and the original MB colours, all of the wires on fuse 1 and 2 will need to be unsoldered, or else you'll get a reading on any of these common wires whatever they feed, unless you can match a wire colour, but it looks like you have several of one colour, madness of whoever did this to your wiring

Many ohmeters have a 200 ohm scale, that's what i would use, but i can't see that on your meter, unless it's the symbol next to the 2K, what do the instructions say? 2K is ok, but not as accurate as 200 ohms when measuring for continuity

Carry on, i'm sure you'll get there, just need to be very methodical, and make exact notes, ie colour of the wire, pin number at connector and pin number at destination, or else you'll just confuse yourself

acbrock · « **Reply #61 on:** May 16, 2024, 15:54:02 »

Awesome thanks for the notes. I will take this Meter back and get one with 200. I will see if the selection next to the 2k is 200. It is an audible tone. but may be it is tone and 200. I will figure that out...

You said " Should mention that all relays or connectors should be unplugged, or else you'll read through relay coils or lamp filaments and this will give a false reading"

Do you mean the relay I am testing or all relays should be pulled before I start trying to trace wires.... Or can I just remove the Wiper Relay and the Blinker Relay?

also
" and the original MB colours, all of the wires on fuse 1 and 2 will need to be unsoldered". So should I take the wires off the Fuse Box and unsolder them and then leave them unconnected? Can I leave the rest of the fuse box connected.?

Thanks for the info! I will start on this! Hopefully it gets me to a spot where I can much better isolate all these damn blue wires.

BobH · « **Reply #62 on:** May 16, 2024, 16:43:30 »

Hello, sorry, yes, just unplug the relay where the wire should go, so the blinker relay and the wiper motor relay. You'll also need to pull the connectors on the head and tailights when you try and trace the turn signal wires, and they also go to the cluster, i'm not sure where this connection is made, somehow the wire/s will go to the cluster 12 pin connector. It would be interesting to know if the turn signal wire colours are correct at the front and real lights and the cluster, black/green and black/white. The instrument cluster should have the black/green and black/white wires there as well

If you can identify any of your wires on fuses 1 and 2, ie any of those blue wires, or other strange colours that shouldn't be there, then you can just remove those for testing, if you check the schematic, you'll see the other colours, the ones you don't need to touch. Having said that you'll probably end up unsoldering them all, as it will be difficult just removing selected wires

acbrock · « **Reply #63 on:** May 16, 2024, 17:56:56 »

Ok. Today once I start. I will not stop until I figure out at least 2 of the wires.

Reading thru the tech manual I could not find a good digram of what the head light plug pins go to. Probably for the rear light too. If you know a link.

BobH · « **Reply #64 on:** May 16, 2024, 18:59:02 »

The connection pins for the headlights are on here, whether yours is US or European

https://www.sl113.org/wiki/Electrical/HeadlightAssembly

I can't see a diagram for the tail light connector in the tech manual, but it looks easy enough to work out what the pins are on here

https://www.sl113.org/wiki/Electrical/TailLights

acbrock · « **Reply #65 on:** May 16, 2024, 19:15:44 »

Cool thanks. My headlight did not match but I will look again and compare to the rear and I am sure I can figure it out.
Traded from a meter with 200 so hope that helps too

BobH · « **Reply #66 on:** May 16, 2024, 19:18:07 »

Just checked again, the connections are for a 71 car, so are probably different for a 230

acbrock · « **Reply #67 on:** May 17, 2024, 01:18:31 »

Ok played around again today. I think this new Multi Meter is crap. It won't even go to 0.00 when touching the probes together. But I started trying to trace wires. I was coming up empty. So I tried testing some other things. So when I connect the battery Fuse one goes Hot. The are 2 Bunches of wires to on the Front and 1 on the back. So I disconnected the battery and removed all wires from Fuse 2. The front 2 of the fuse had 2 sets of wires attached.Set 1 had 2 Wires, set 2 had 3 Wires. My guess was the 2 Wires were Horn and Cigarette Lighter. The other set of 3 was Washer Relay/Motor and Pump. I grabbed my power inverter and connected the set with 2 Wires. Lighter light up. I dont have horns so could not test the horn. When I put power to the other 3, I got power reading out of the Washer Relay but not the Motor or the Pump. My hope was sending power thru these wires I should have gotten 12v on one of the pins on the connector but I did not.

I did the same thing with Fuse 1. Things worked that should with power, like the Entrance light, map light , clock...
But no power to any pin in the Connector?

Also shouldn't Fuse 2 go Hot when I turn the ignition to the 2nd Position? It did not? I did not want to start the car because of everything loose. Does the car need to be running to Active the 2nd Fuse or do I have another Gremlin to trap and Kill.

I am going to review everything tonight. Probably with some booze and then decide if I need to unwrap a wires and see what I find. Taking the wires off of Fuse one there was a bulge and when I unwrapped a little the was a wire with a connector on it wrapped up and folded backwards. I will test that tomorrow and if I can track down what that is.... Thanks for all the support. This car has been soo much fun... Not so much these last few days.

Leester · « **Reply #68 on:** May 17, 2024, 14:27:49 »

A couple of thoughts for you.

I just don't see how your multi-meter isn't giving you something to work with Ohm wise.

Even though you don't have horns, its possible that you still have the wireing where it attached to the horns. You could run the same check you ran to confirm the cigarette lighter on those wires and see if you have power. Seems like you are aware of the danger working with live voltage and being very careful.

I do believe that with ignition in position 2 you should get power at fuse 2. Maybe BobH or someone else can confirm. I think earlier someone may have mentioned that your wiring in the ignition switch may not be working correctly. Under normal conditions, I'm sure the car does not have to be running to get power to fuse 2 with key in position 2. You were wise not to start the car.

If you got power on the relay connector pin that corresponds with terminal 56b on the relay you are making progress. You should get power there from fuse 2. On my car, the connector plug for the ww motor actually has numbers next to the female pins. I get power at pin 4 (the number on the connector - not the motor) directly from fuse 2 when ignition is on.

The little wire that was wrapped up may be part of the disabled "flash to pass" feature. In an undisturbed car that wire was white with red and blue tracers. There are many posts on that which you can find with a search. But I would leave that rabbit hole for later.

I really think you need to find an Ohm meter that works for you. I only resorted to testing with voltage as a last resort and I was really distracted worrying about the consequences.

Cees Klumper · « **Reply #69 on:** May 17, 2024, 15:47:14 »

As an aside here, since electrics and electronics have always been a weak spot of mine, as evidenced by my difficulty in following the various twists and turns in this thread, I finally decided to 'go back to school' and order two textbooks on 'diagnosis and troubleshooting of automotive electricity and electronics', both authored by a Jim Halderman, 1,400 pages in all. That ought to do it!

BobH · « **Reply #70 on:** May 17, 2024, 16:05:35 »

I haven't really investigated the wiring loom on my car, luckily i haven't needed to. Presumably the wiring loom from the 12 way connector, which we've established has been replaced, due to the change of colours, joins to some of the original coloured wires, such as the turn signal wires. Where does this join occur, is it a connector, or is it on the actual appliance, ie the front lights, rear lights, where do we think, has this been investigated? Or do the new colours make the whole journey from the 12 way connector to destination, was the whole car rewired at some point?

acbrock · « **Reply #71 on:** May 17, 2024, 17:51:27 »

Interesting. Yes I think that wire that is folded back is the color you mentioned. I am going to go return these multimeters and get a new one and different brand today. I will do a few tests that I have been able to confirm and then I am going to peel back some of the wrap at the appliances and at the switch. Hopefully at the appliances the colors will be correct and then I can peel back the wrap on the connector and hopefully get to where these wires were spliced in.... or find that these new blue colors go all the way which would help too.

Today is the day!!!

BobH · « **Reply #72 on:** May 17, 2024, 18:21:47 »

Quote from: acbrock on May 17, 2024, 01:18:31

...So when I connect the battery Fuse one goes Hot. The are 2 Bunches of wires to on the Front and 1 on the back. So I disconnected the battery and removed all wires from Fuse 2. The front 2 of the fuse had 2 sets of wires attached.Set 1 had 2 Wires, set 2 had 3 Wires. My guess was the 2 Wires were Horn and Cigarette Lighter. The other set of 3 was Washer Relay/Motor and Pump. I grabbed my power inverter and connected the set with 2 Wires. Lighter light up. I dont have horns so could not test the horn. When I put power to the other 3, I got power reading out of the Washer Relay but not the Motor or the Pump. My hope was sending power thru these wires I should have gotten 12v on one of the pins on the connector but I did not.

I did the same thing with Fuse 1. Things worked that should with power, like the Entrance light, map light , clock...
But no power to any pin in the Connector?

Also shouldn't Fuse 2 go Hot when I turn the ignition to the 2nd Position? It did not? ...

https://www.sl113.org/wiki/Electrical/Fuses

Fuse 1 powered at all times
Fuses 2 to 6 are linked together, all get power when the ignition switch is turned to position 1

So you'll need to investigate why fuse 2 is not getting power, i think you said you'd never removed the ignition switch, perhaps time to bite the bullet!

acbrock · « **Reply #73 on:** May 17, 2024, 20:26:44 »

oof. Ok I guess I will read how to get the ignition out. Seems like it the whole dash is coming out again

Initial tests today. When I supply power to the fuse 2 Wires. I get the lighter again but don't see any power in the switch, was hoping to find the Horn Cable. Then switched to the other set of wires...

Relay I get power but not on 56 but 56B?
And still no power to the wiper Motor on Pin4. So I am going to start unwrapping some things...

Cees Klumper · « **Reply #74 on:** May 17, 2024, 20:51:54 »

On my 280 SL, the ignition switch is two parts: one, the front chrome tumbler part the key goes into, and then plugged into the back of that, the actual electrical switch that the connector plugs onto. My car was beginning to be difficult to start due to the switch starting to fail. I think for around $70 I got a complete new switch and problem solved. The chrome tumbler part did not have to come out, I only needed to remove and replace the electrical switch part at the back of the tumbler. 230's may be different?

News:

Author Topic: Turn Signal Relay Buzzing? (Read 5527 times)