Hello this is the first time I have sought help in the forum. My car is a W202 C250 turbodiesel. A strange thing happened today, my partner was driving normally when all of a sudden and without pressing any switches the hazard warning lights started flashing and she couldn't turn them off. The car is parked up at home now and locked with the fob and they've stopped. Any ideas please?
W202 Hazard Warning Lights Flashing Constantly.
- Thread starter Cymon
- Start date
Possibly the alarm battery.
exvolvoman
Active Member
Does the alarm siren stll work, if not, suspect the alarm battery as Killerhertz says.
No the alarm siren is not working, and where can I find this battery? Is it possible to disconnect it so she can still use the car?
Petrol Pete
Hardcore MB Enthusiast
Under the left front wheel arch, remove/pull back liner , un plug siren and forget about it forever.
Pete can you be more specific please, forward of the wheel or towards the back of the car? There’s a big hole in the bottom of the liner forward of the wheel and I had a look and couldn’t see anything
Attachments
Back of the wheel, not the front as per your pic. You will need to remove the wheel as the liners interlock.
Once you access it you will need a special torx bit with as there is a pin in the centre of the bolt.
Note if your car is nicked and it has the alarm disabled, should insurance company fine out your screwed.
Once you access it you will need a special torx bit with as there is a pin in the centre of the bolt.
Note if your car is nicked and it has the alarm disabled, should insurance company fine out your screwed.
Petrol Pete
Hardcore MB Enthusiast
On a C class 203 You remove the plastic wheel arch liner front left wheel ,you can do it by turning the steering all the way to the left and pulling the liner away at the rear of the arch but removing the road wheel makes life easier.
You will see the metal plate that the sounder is bolted to, access is easy from there on. Yours is a 202 but I believe it is in same location. The batteries are inside the sounder unit and they often rot out and destroy the PC board within.
Sometimes they can be repaired and re furbished units can be bought on line or new from MB. And alarm on any car is only as good as the person who pays attention to it and does something about it. If you want to replace or repair it that's up to you.
You will see the metal plate that the sounder is bolted to, access is easy from there on. Yours is a 202 but I believe it is in same location. The batteries are inside the sounder unit and they often rot out and destroy the PC board within.
Sometimes they can be repaired and re furbished units can be bought on line or new from MB. And alarm on any car is only as good as the person who pays attention to it and does something about it. If you want to replace or repair it that's up to you.
- Joined
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- 65 Plate E350 CDI Convertible, 2006 CLS 55 AMG, 1997 C230K, 1999 C43/55 AMG
Hi,
Yes 182 Is the alarm siren, and it is the front part of the arch liner near enough behind the bumper.
Just unplug it and tape up the plug.
I take it your car is a facelift model? (1997 on) as the siren can be in a slightly different on the earlier prefacelift cars.
Yes 182 Is the alarm siren, and it is the front part of the arch liner near enough behind the bumper.
Just unplug it and tape up the plug.
I take it your car is a facelift model? (1997 on) as the siren can be in a slightly different on the earlier prefacelift cars.
Hi Andy, the car is March 1997 and is prefacelift.
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- 65 Plate E350 CDI Convertible, 2006 CLS 55 AMG, 1997 C230K, 1999 C43/55 AMG
Hi,
If it is a pre-face lift car then the alarm siren if fitted is under the bonnet on the passenger side though I suspect disconnecting it for a prolonged period of time it might cause more issues possibly problems with the immobilizer.
If you're alarm system is the same as my old C230K, I would be looking at the alarm control unit which is fitted in the forward part of the passenger footwell under a steel plate alongside other control units
To identify it it is made of black plastic and a bit bigger than a fag packet, it will also have Pt.No. starting with a Q.
These alarms were generally fitted at the point of entry into the UK, so the wiring to this control unit wont appear to be as neat, I believe it is in this area that they spliced into the indicators, check the wiring and any exposed joints, there are normally some inline fuse holders here which in my case had corroded and needed replacing.
There was talk of a white colored relay in the boot area near the boot fuse panel apparently something to do with the indicator activation which i did find and removed cleaned etc.
If it is a pre-face lift car then the alarm siren if fitted is under the bonnet on the passenger side though I suspect disconnecting it for a prolonged period of time it might cause more issues possibly problems with the immobilizer.
If you're alarm system is the same as my old C230K, I would be looking at the alarm control unit which is fitted in the forward part of the passenger footwell under a steel plate alongside other control units
To identify it it is made of black plastic and a bit bigger than a fag packet, it will also have Pt.No. starting with a Q.
These alarms were generally fitted at the point of entry into the UK, so the wiring to this control unit wont appear to be as neat, I believe it is in this area that they spliced into the indicators, check the wiring and any exposed joints, there are normally some inline fuse holders here which in my case had corroded and needed replacing.
There was talk of a white colored relay in the boot area near the boot fuse panel apparently something to do with the indicator activation which i did find and removed cleaned etc.
Thanks Andy, armed with this information I'll have a look this weekend.
Petrol Pete
Hardcore MB Enthusiast
Oops, Sorry Cymon I gave you duff advice on the position of the siren. I assumed it was very similar to a W203, I didn't know there was a 10 year difference between your car (W202) and the W203 I did this job on. Sorry.No problem Pete, I hadn’t taken it off as I was waiting for the weekend.
- Joined
- Nov 27, 2004
- Messages
- 4,800
- Location
- Southampton
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- 65 Plate E350 CDI Convertible, 2006 CLS 55 AMG, 1997 C230K, 1999 C43/55 AMG
Pete you would of been correct if it had been a face lift 202, as it is in the same position as the 203.
Petrol Pete
Hardcore MB Enthusiast
I would advise replacing the alarm, not expensive at around £120 as removing it will affect your insurance.
Most policies include fitment of factory alarm within the policy wording.
Most policies include fitment of factory alarm within the policy wording.
