BAS Light

[ldare]

Hi
Ive had my W163 six weeks and now Im on to my 5th failure. Either bad luck or an awful car.


The drive belt either snapped or was thrown by a failing tensioner. Both now replaced.

As the car was driven onto the recovery truck the BAS light came on. I though this was because there was no power to the power assisted brakes. Since the repair Ive tries various versions of the left right full lock reset as advised on a number of sites but cant get the light to go out.

Im not sure I can face another repair bill.......

Any advice?

Ta
Louis

 

[ExMercTech]

If the light won't go out it means the fault is current.
Your need the codes read by a dealer or Indy using Star.

Could be a simple repair as a break light switch but you do need the codes read.

 

[ldare]

If the light won't go out it means the fault is current.
Your need the codes read by a dealer or Indy using Star.

Could be a simple repair as a break light switch but you do need the codes read.

My dad has a basi OBDII scanner? Will that do? Mine's the 2003 model so there isnt the brake switch in the footwell. I am a bit annoyed the mechanic that changed the drive belt didnt notice the light as he had the kit to sacn on him. He's away this weekend.

I dont have any brake lights at the moment so would love to find out asap whats wrong.

Ta

 

[ldare]

Basic not Basi LOL

 

[ldare]

Ive checked the fuse. That was ok.

 

[bob6600]

If your ML has an OBDII port try it and see what it scans.

 

[mersum1es]

Brake light switch?

Wiring harness of ABS is prone to fail in ML-class, but I think it would cause ABS light as well.

 

[ldare]

Brake light switch?

Wiring harness of ABS is prone to fail in ML-class, but I think it would cause ABS light as well.

2003 on didnt have a brake light switch, Id have expected the ABS light to be on too. Cruise is working too which some report isnt working with this light.

Id love to know, if thr brake lights arent working because the BAS light is on, or if the BAS light is on because the brake lights arent working. The steering doesnt feel as it did so I'll get the tracking checked. Im wondering if moving it (as instructed by the recovery company) without power steering has had an effect. The recovery truck couldnt get to the car where in was when the drive belt failed.

I know I really need to get the fault codes scanned but its not easy at the weekend and Ive had to use the car tonight without brake lights :-(

Cheers
Lou

 

[ldare]

I'll pop down Kwic Fit earlier get a four wheel align to be on the safe side. It does feel like doing a three point turn with no power steering has affected the alignment? Maybe just in my head but light did come on after the three point turn.

 

[ldare]

I'll pop down Kwic Fit earlier get a four wheel align to be on the safe side. It does feel like doing a three point turn with no power steering has affected the alignment? Maybe just in my head but light did come on after the three point turn.

Fair play to Kwic Fit they did a needed wheel allignment and didnt charge as the light stayed on. Hopefully a proper code read tomorrow

 

[ldare]

It's the steering angle sensor :-(

does anyone know where i can get a guide on how to replace just the sensor?

Ta
Louis

 

[Auto-mobile]

Comes with the column.

 

[andy27168]

2003 on didnt have a brake light switch, Id have expected the ABS light to be on too. Cruise is working too which some report isnt working with this light.

Id love to know, if thr brake lights arent working because the BAS light is on, or if the BAS light is on because the brake lights arent working. The steering doesnt feel as it did so I'll get the tracking checked. Im wondering if moving it (as instructed by the recovery company) without power steering has had an effect. The recovery truck couldnt get to the car where in was when the drive belt failed.

I know I really need to get the fault codes scanned but its not easy at the weekend and Ive had to use the car tonight without brake lights :-(

Cheers
Lou

Hi,
Can I ask what makes you think a MY2003 on didn't have a brake light switch? Friend of mine has a MY2004 ML 270CDI, and it most definetly has a brake light switch as I replaced it for him.
The Brake light switch on a 163 was also subject to a recall if I remember correctly, with the issue you have I would replace it before doing anything else.
If you look immediately/directly above the brake pedal you will see the switch, it will look very similar if not the same as the one in the link below.
BRAKE LIGHT SWITCH MERCEDES M-CLASS (W163) ML 55 AMG (163.174) 347BHP Top German | eBay
Buy a genuine one only about a tenner, they will have it in stock, very quick easy to change, cheaper than getting it plugged in and if it solves your issue happy days!.

 

[ldare]

Hi,
I've now ordered sensor and column off eBay MERCEDES W163 ML 270 CDI AUTO STEERING COLUMN A1634600516 / 1634600090 | eBay

I 100% do not have a brake light switch (I wish I did), and also checked with online guides etc. Mercedes were supposed to have stopped using them during 2003, it's possible mine was made just after they stopped and your friend's 2004 was born just before mine. Sadly these car's were made in America so could have sat in a large compound for a while.

Thanks for the recommendation tho.

Thanks
Louis

 

[andy27168]

Apologies spoke to mate today, and he reckons it was his uncles X plate ML270 that I replaced the brake light switch on though I still find it hard to believe that there wasn't one fitted.
I will check for definite for my own piece of mind next time I am at his workshop.

 

[chrispynuts]

Next one !!!??? Cant delite this one

 

[chrispynuts]

Hi the brake light switch is mounted in the brake booster right hand side of the master cylinder looking towards the back of the car

 

[andy27168]

Hi,
I have checked on the official EPC directly using my mates chassis no. his ML is definitely a 2004 model as it has code 804, and according to the EPC it most definitely has a brake light switch MB Pt.No. A 001 545 95 09, this number replaced the original A 001 545 31 09.
If you want me to check on the EPC your chassis number is the same (which I have no doubt it will be), I pay for access to the official EPC so it is as accurate as you're MB Dealer's.
Please check, remove the lower dash panel and look up you will see it below is a video as a guide.
[YOUTUBE HD]AWjIZBuPLZ0[/YOUTUBE HD]

 

[andy27168]

Hi the brake light switch is mounted in the brake booster right hand side of the master cylinder looking towards the back of the car

The item in the face of the brake booster is described in the EPC simply as a Sender Unit, this I believe is something to do with the BAS.
The switch above the brake pedal is described as Brake Light Switch in the EPC. Both parts are applicable to a 2004 model.

 

[chrispynuts]

The item in the face of the brake booster is described in the EPC simply as a Sender Unit, this I believe is something to do with the BAS.
The switch above the brake pedal is described as Brake Light Switch in the EPC. Both parts are applicable to a 2004 model.

There is no brake light switch fitted above the brake pedal on the 2003 ml270 I own one and had a problem with the BAS etc system there is two switch assemblies fitted fitted to the booster on that model