Fast flashing Hazard lights.

[daf123]

Been suggested that I start a new thread for this.

http://forums.mercedesclub.org.uk/showthread.php?t=36912&page=2

Has anyone resolved this problem where each and every time you lock the car using the key-fob the hazard lights start flashing at twice the normal speed, the interior light comes on and there's no alarm sounding?

I have a 2002 C-Class which has four contact switches on the doors and one on the LHS of the bonnet. If it is a switch, as suggested in this thread, how can I test each switch to see if it is one of these?

If it's just a case that the alarm is actually going off, why isn't there any sound? Could there be a problem with the alarm unit?

I have replaced the battery thinking that this was the problem (car had been idle for 4 days) but obviously this has had no effect. At the moment I lock the car using the key and not the key-fob as this doesn't arm the alarm. I don't fancy a trip to a Main dealer due to hassle and cost! I doubt whether any of this could be picked up on a diagnostic test, or could it?

 

[wullyuk]

It's the alarm siren under the plastic cover within the passenger wheelwell.

I have one on order and it should be with me tomorrow. In the short term i disconnected the wiring plug into the siren.

 

[television]

Loads gone down this year Wully

 

[wullyuk]

Loads gone down this year Wully

When i first looked at mine i was suprised by the corrosion on the bracket etc so decided to buy all the components that went with it.

Be careful when ordering a replacement, the W203 part number has been superseded by a A171 number.

On mine:-

A2038203826 £91.43 ex VAT
A1718202526 £71.30 ex VAT

I went for the A171 number so lets hope it's ok!

 

[Cole@MBS]

That part number you have been given is the new one, only differnce is that the old siren use,s a bolt to hold it in, where the new one has a 13mm nut to hold it in!

 

[daf123]

It's the alarm siren under the plastic cover within the passenger wheelwell.

I have one on order and it should be with me tomorrow. In the short term i disconnected the wiring plug into the siren.

We have a winner!

Took it to a local garage and plugged it into his 'Snap On' diagnostic tool. This detected a 'fault with the alarm' but gave no further detail regarding sensors or other problems. The mechanic suggested that I had to bite the bullet and go to the Dealership for a diagnostic test (£30). They informed me that it was the siren part of the alarm and they confirmed this by swapping in a new one to test whether it would lock and unlock OK (fair play to them).

The part was £75 and the total bill (diagnostic, labour and parts [plus a couple of other light bulbs that were faulty]) came to £150. Not as big an ouch as you get at a Merc garage but at least the fault was gone and my wife was now a happy bunny.

While supping my Americano coffee, I could see the mechanic at work on the car and could not believe how low down, near the passenger side front wheel the alarm siren was located. Strange design decision.

Thanks again.

 

[Lowey]

Hi

Where can I find the siren as I can hear it but it sounds like a strangel
A Strangelled Chicken. !

 

[television]

Hi

Where can I find the siren as I can hear it but it sounds like a strangel
A Strangelled Chicken. !

Top at the rear of the nearside wheel arch liner under a plastic cover

 

[shaun2209]

How can I test my alarm? As I don't hear an audible warning when locking the car, all I get is the flashing indicators - 3 times I think.

 

[television]

How can I test my alarm? As I don't hear an audible warning when locking the car, all I get is the flashing indicators - 3 times I think.

Lock the car with the remote, then use the key and open a door and the alarm should go off

 

[yeh yeh]

To test the alarm all you have to do is to open the window, any window,it doe's not matter, arm the alarm with the remote, wait maybe a minute or so, then open the door, if the alarm is working, it will sound.

 

[yeh yeh]

Sorry, I should have said you open the door from the inside of the car, hope this help's.