My Crossfire failed registration (in Australia) as the indicators are flashing too fast.
I know that this topic has been discussed before but I didn't see reference to this particular issue on any of the threads.
The engine fuse box has two large relays (about 1" cube) at the rear and the black one is meant to be the flasher relay.
I removed this relay (part no 002 542 21 19) which is referred to as a Mercedes Turn Signal Relay and checked the resistance
which seems to be normal, about 90 ohm, indicating no fault in the relay.
The weird issue is that the indicators are still flashing (fast) with both relays removed - I can't understand that.
As the car is presently unregistered and off the road, I would appreciate experienced advice egarding this problem.

Thanks all

Ron

 

Forgot to mention that the hazard lights are working properly, at the normal speed, with both relays being either in place or removed.

Ron

 

Have you checked that all of the bulbs are working? Are they LEDs?
Also the inside of the turn signal switch may be dirty. With the car off, you can spray a little bit of contact cleaner into the switch. Move the stalk a bit while spraying.
Let it dry after spraying, then try it.
Maybe that will help.

 

Check your hazard switch. That has been known to at least prevent the flashers from flashing. Might be causing them go too fast.

 

Thanks for the replies.
Flashers still going fast.
My comments are:

All bulbs are working, external and internal
The are no LED bulbs in the system- all bulbs are as per spec.
Indicators were flahing properly but became faster with time.
I cleaned all contact, no change.
Hazard switch is working properly.


Am I missing something obvious?

 

Strange... In the good ole days the flasher went fast when one lamp filament in the circuit was burned open (no light). These newer circuits are different as I understand it but I have no idea why yours is acting like a bulb is out (in the left/right turn signals). I would check (as a suggestion) the bulbs brightness at night when it is dark enough to see if one bulb in the circuit is much dimmer or much brighter. This might show up as a flashing faster symptom (again, it is just a suggestion to try). Good luck (I hope one bulb is brighter or dimmer than the others).


.

 

It's not expensive nor time consuming. I would try replacing the directional bulbs two at a time and see if anything changes.

 

STOP. The relay in the fuse box is for flashing the lights when the SKREEM indicates "Lock" or "Unlock".
The turn signal/four way flasher is a function of the BCM (Body Control Module). If you want to troubleshoot this, download the service manual and follow the diagrams in the wiring chapter, turn signal section.

The hazards flash all four lights. This means you have enough current flowing so that the flasher works normally because there are four bulbs, even if they are not factory-spec, there is probably enough current for the flasher circuit to act normally.

The turn signal function is two lights, if not enough current is flowing, you get a fast flash, caused by:
1) One light is out.
2) If the lights are not the same as the factory bulbs, their current may be lower, too low to make the flasher work at the right speed.

Another possibility is that the flasher circuit in the BCM may have an issue - replacing the BCM would be the way out of that one.
But I think you have a bulb out OR you have out-of-spec bulbs.

In any event, you cannot troubleshoot this unless you understand how things work, and that means you should download the service manual.

 

Hi! I had a fast flashing right indicator.

I found that the contacts in the bulb holder (in the headlight assembly) had not been touching properly and were arcing. The arcing burned a hole in the contact on the bulb holder. I filled the hole with some solder and popped it back in. Good contact was re-established and indicator now behaves as normal.

 

Thanks for the follow up and solution. This is good historical data in case somebody else has this issue.

 

All good now. Flashers working properly and the car now registered and back on the road.

I followed good advice and replaced all bulbs and then I found that the problem was, as suggested,
bad contacts in the bulb holders within the headlights.

Looked like this problem happened before as there was an attempt to fix up the contacts in the bulb holders by adding
solder - I cleaned it all up, carefully added solder and problem gone.

Tomorrow the car is going in for body repairs after negotiating with the insurers (since the February 2024 accident) of the party
at fault. It is going to cost them quite a bit owing to parts scarcity, cost of skilled labour, cost of replacement car for the duration, etc.

Anyway, thanks everyone for the good advice and I hope to have a properly presented car back on the road soon.

BTW the CCs are becoming very rare in Sydney.

Ron

 

I also want to thank you for posting a follow up message here.
Many people resolve their problems and never return here to the thread they created looking for help.
These follow up posts may be helpful to someone else in the future.

 

My indicators on the right side of the car (UK driver side) have started to fast flash. The left side flash correctly.

I will check and probably change both front and rear bulbs but if that doesn’t’ fix it I’m wondering where to start

 

Check the contacts in the bulb holders

 

Have some contact spray. So will try giving the bulb holders a spray

 

Read the thread above. Your problem is likely to need more than that! An easy fix however.

 

If it's not too much trouble, would you be able to post a picture showing the repair that you made? I would like to see where it was, just for future reference. No rush, whenever it's convenient for you.
Thanks in advance,
John

 

I’ve read all the posts above and presume you’re referring to also checking the bulb holder contacts in the headlight assembly. I’m a bit confused as to which bulb holder contacts in the headlight assembly I should be checking

 

The contacts in the actual plastic holder that you remove which the bulb slots into

 

If one side is working normally, then on the side that flashes fast you have:

One light out.
Aftermarket bulbs that flow less current than factory spec.
A bad socket (that light will flash dimly or not at all).

Replacing front and rear bulbs with a factory-spec bulb will tell you if it was a bulb, if factory-spec bulbs do not work right, I'd blame a socket - the front sockets are known trouble. The contact between the "bulb carrier" and the little tab in the headlight housing tend to become pitted. I flowed a blob of solder on the tab on the bulb carrier adn it fixed mine. See, the tab wears down/burns away and contact is spotty at best. Building it up with molten solder seems like a good fix, at least, it has worked for me.

You should know that replacement sockets are available but do not search for a "Crossfire" part, the parts stores computers do not list the Crossfire as a 'fit' for the part in question. I can't remember what someone searched for but they found them in a parts store, on the shelf. I think they were for some other Mercedes or BMW car.