Mercedes A Class with water in battery compartment

batman2000

I took our car to the Mercedes garage yesterday because of an intermittent failure to start. It turns out there was water (don't know how much) in the battery compartment causing "corroded wiring connector/loom" including the starter motor feed. The garage sent photos but I'm not sure I'm at liberty to share them (?).

A quick search of google and it seems I'm not the only one and that it's a 'common' fault with this car. The garage mechanic mentioned the water was getting in via the grills near the front windscreen wipers due to a drain being blocked... does that sound about right??? He wouldn't talk money for repair, instead preferring to strip the car further and look for more damage, hoping it can be cleaned up without any major issues. Hmm.

So I'm waiting for another call from the garage today and I guess I'm wondering (a) where does the liability lie with this? Should we have known to keep the 'drain' clear? I didn't even know it was there! The car has been regularly serviced by Mercedes, the last time about a month ago. (b) would this be covered by insurance? We have comprehensive cover but I don't see any mention of water damage on the policy (I'll have another look, in case I missed it).

BTW, the car is a 2006 A150 (W169) model, with low mileage for it's age (in case that matters!). I've seen people online quoting repair bills in the thousands for similar problems....

Thanks for reading

bengalknights

Unfortunately as it not within Mercedes warranty it wont be covered by them however should be a simple enough water proofing and replace fix depending on how far it got.

batman2000

bengalknights wrote: »

Unfortunately as it not within Mercedes warranty it wont be covered by them however should be a simple enough water proofing and replace fix depending on how far it got.

The corrosion on the photos looks pretty bad (like the end of a battery when it leaks) and there's quite a lot of verdigris too. I can also see rust in other places. I'll wait and see what the garage comes back with.

Preparing myself for the worst, so it can only be better! Haha!

daveyjp

We have the same car, I also owned a B class for 5 years. I was not aware of the problem

However its a preventative maintenance issue. When you have the bonnet up for regular oil, water checks always clear out the drainage grilles around the windscreen wipers.

They do get blocked with leaves and these break down and block up the drainage channels.

10 minutes once a month to do the checks and clear the channels isn't onerous.

wgl2014

Not just Mercs that have this issue. Water runs off the bonnet or windscreen and flows down past the battery and through a couple of small diameter drain holes before dropping onto the road. The holes get gummed up with mud, twigs, leaves etc and then the water backs up and floods any available spaces. Easy to keep on top of when you know it could be an issue, just poke any dirt out with a wire coat hanger.

batman2000

Thanks... we do clear the grills of leaves and such, and have not had this problem with any other car :-/.

My impression from reading around is that the battery compartment on the A Class is positioned in such a way that makes the car more susceptible, but I could be wrong. The compartment is under the driver's seat and the drain hole isn't accessible. I would have thought that it would be checked on a service, if it was a known issue? Maybe I'm expecting too much.

No news from the garage yet.

batman2000

Here's what I think has happened (scroll down to see the drain valve):

http://www.aclassinfo.co.uk/page.10.169.htm

Hindsight is a wonderful thing

batman2000

Update: we got the car back after having the corroded starter loom replaced and a new fuse box installed. The garage discounted the hourly rate and reduced the number of hours work (as a goodwill gesture) and we paid a little under £500.

Since we got the car back 6 days ago, we've had the same intermittent problem starting it (e.g. no response to first turn of key, starts on second turn), and last night after a day of heavy rain the car completely refused to start.

So... the car was serviced last month, and the drain hole(s) presumably cleared during the work we had done. And the problem's still there.

I'm ringing the garage again this morning, but don't want to throw good money after bad... any suggestions? The car is 10 years old, 50,000 miles on the clock with full service history (all done with Mercedes).

knightstyle

Just a thought as I am not a Mercedes owner but if it is a diesel and starts easily on the second attempt it could be the cold engine waits for glow plugs to heat the combustion chamber.

batman2000

knightstyle wrote: »

Just a thought as I am not a Mercedes owner but if it is a diesel and starts easily on the second attempt it could be the cold engine waits for glow plugs to heat the combustion chamber.

Thanks... but it isn't a diesel. It just wouldn't start at all last night and it was the first day it had rained a lot since having it 'fixed' (coincidence?).

Just spoke to the garage and they'll take it back in, probably tomorrow.

---lee---

Modern diesels don't need glow plugs to start. They are there to reduce emissions and to assist in very cold temps. The glow plugs are manually controlled on my car and I rarely use them.