Emergency hazard switch - testing and fitting

[Merc_Girl]

Hi folks

Me again!?!?

So, I’ve recently purchased a period (I have an early Pagoda), what I would name as a ‘hazard warning switch’.
Slight flaw in my plan is that I don’t know how if it works or indeed how to wire it in, so only minor problems!?!?!?

So, to summarise, I’m calling out to all electrical pagoda gurus out there to :
a) advise how I can test to see if the system still works
b) how can I hard wire it in? (I’ve looked on the wiring diagram in the technical manual but couldn’t see a reference to hazard warning switch

As always, any advice greatly welcomed 🥰

[WRe]

Hi Katie,
your new hazard switch should have following terminals:
New                                                                                                Old
15:   + ignition switch                                                                      (15 - black/red/green)
30:   + battery                                                                                 (30 - red/blue/white)*
31:   - battery/ground                                                                     (31 - brown)
49a: flasher (exit, clocked)                                                              (54 - black/white/green)
R:     flashing light right                                                                    (R - black/green)*
L:     flashing light left                                                                       (L - black/white)*
The new switch/relay replaces the old flasher relay (wire colours may vary).
* flasher plug
BUT: Differences such as 230-250-280, US - Europe, manual transmission - automatic transmission, etc. can lead to differences in circuit diagrams, pin assignments and cable colours.
... Wolfgang

[Pawel66]

Katie, please post a picture with pin connectors numbers.

[DavidAPease]

Hi, Katie,

I, too, have a 230SL and have purchased one of these switches.  I've studied the wiring diagram and understand how they connect to the existing wiring.  However, building the wiring harness with the correct plugs is somewhat challenging, including sourcing the connectors.

I believe that our member Leonardo Peterssen (lpeterssen) has offered to make them (for a price, of course).  Just another option...

           - David

[Merc_Girl]

Will do David when it arrives! It’s in New York and I’m waiting him to drop off in December when he comes to visit 🥰

[Merc_Girl]

Hiya, presume could splice the wiring together ? 🥸

[BobH]

I'm not sure this old style hazard switch/blinker relay will work with LED's, unless you keep the existing blinker relay (i believe you recently fitted a new style electronic relay?) and use this hazard switch to switch the other relay.  Has anyone done this successfully?

So, having read more on this, seems the early hazard switches, which were supplied as an option, work alongside the original blinker relay, not instead of, so it will switch the old style relay, or a new relay if you've replaced it when fitting LED's

[Pawel66]

I think David's idea to ask lPeterssen for help is a good one. You can probably ask him to make you a harness so that you will have it on a plug and play basis...

Also, as BobH says, if you have LEDs there it may not work. The older types of hazard switch relays were, sort of, taking over the blinking function form the regular blinker relay, generated their own blinking and sent to L and R blinkers. I think this blinking function was done the "load" way - if so, it may not work.

[lpeterssen]

Dear friends, David

That is right I have the special sub harness to connect those early style falsher/hazard relay available on my store.

Here the link:

https://wiredoktor.com/products/mb-w113-hazard-relay-sub-harness

Best regards
L.Peterssen
Www.wiredoktor.com

[lpeterssen]

Katie:

You may add something like this on the output side of flasher /hazard relay.

See:

https://a.co/d/hP0mEtr

Best regards
L.peterssen
Www.wiredoktor.com

[lpeterssen]

Here a photo of how the subharness looks so that you can install it without modifications to your main harness

[Merc_Girl]

Thanks everyone for your input
Apols for radio silence!

Mates arriving from US with said switch, so preparing for battle!
Well done for remembering I have LED lamps!?!?

I.have a ‘modern’ emergency flasher switch which was installed before I bought Bessie. Maybe I can bastardise that 😱🤣

[Merc_Girl]

Hi folks
So we’ve tried the switch but can’t get to work

Is there any notes anywhere on how I can test the switch itself to ensure it is fully functional, or how to refurb, to identify if it is the switch itself at fault or that the leds are causing the problem

Thanks again everyone 😁

[Pawel66]

Can you post picture of the connectors so that we see the numbers?

[Jack the Knife]

Be sure to check fuses!

[Merc_Girl]

Here you go 😔

Ah, just spoken to ‘my man’ and he has confirmed the switch itself is faulty 😔

Does anyone in UK know a business who can repair such things (had enough of export forms and import duties!!!)🤬

[Pawel66]

Maybe then just to make sure:

- hook power to 30
- hook ground to 31
- hook bulb to L or R
- hook bulb to ground

Switch it on, it should be flashing.

The 54s are for regular blinkers, you may not need them. Your regular blinker will continue taking care of that.

This is how I wired mine. However, Leo is proposing more professional way of doing this.

As for repair, it may be as simple as cleaning the points or it may be very difficult to repair if not impossible.

Let’s see what Leo says, he is the Guru.

By the way: I am not sure if this switch is the one used in our cars. It has the K pin, which is for control lamp. But in our cars control lamps are hooked to blinkers on either side. We do not need the K pin. I think it would work anyway, it is just different type of switch.

[BobH]

Here you go 😔

Ah, just spoken to ‘my man’ and he has confirmed the switch itself is faulty 😔

Does anyone in UK know a business who can repair such things (had enough of export forms and import duties!!!)🤬

I wonder how your man tested it, in the car or on a bench?. As Pawel says you'd need to connect a filament lamp to L&R to make it work.  If they tried testing it in your car it won't work with your LED indicators, as they won't draw enough current to activate it

it will take a bit of figuring out to make it work with your modern indicator relay and LED's, it may need an additional standard relay or an additional indicator relay

I wonder if anyone else has tried this with success

[gordon]

The one I bought was faulty. As a member of the UK Mercedes  club the technical guy (Jeremy Stevens) rebuilt mine with new parts and provided me with a schematic for me to make up the wiring all at a reasonable price

[Merc_Girl]

Great, thanks for the tip 🥰

[WRe]

HI Katie,
If I see it correctly, the contacts 54BL and 54S are used to make this emergency hazard switch/relay share the existing relay by interrupting the connection 54 (old notation) or 49a (new notation) to the flasher relay. Otherwise, if both relays were used at the same time, all flashing lights would light up permanently.
...Wolfgang

[Merc_Girl]

Thank you! 🥰