ABS light not on / ESP logged ! fault

[Mad smart person]

Greetings All, here's a new one, I've searched this site already and nothing like what I have. The problem is the ABS light. Turning the ignition on, should see the light illuminate and then extinguish. In this car, the ABS light does not illuminate at all. The instrument cluster has been removed and the bulb is fine, swapped a couple of bulbs about and in other positions they're fine, just not in the ABS position - so nothing wrong with the bulb. Questions are, where does the voltage come from to turn the light on and what enables the light to turn off. Thoughts are, that, a) the voltage is not getting to the light to turn it on. Or b) whatever enables it to turn off, has it turned off all the time, so it won't turn on to begin with.
Had the car connected to a Star machine and there's a 'logged' fault with the ESP but not (F) or (f), just a (!) - what's that mean??
Currently the battery is disconnected it will remain that way for about 12 hours, I'm not holding my breath on that one, for being the fix.
Brake lights and gear changes happen as the should, it drives fine, accelerates fine and stops fine. I've not stomped on the brakes though to see if the ABS actually works.
Yes, this is a most different fault, normally the ABS light stays on.
Has anybody got any thoughts, before I pull the car to bits???
Cheers, Happy Smarting, Ian.

[heinkeljb]

Re: ABS light not on / ESP logged ! fault

As you say, that's a new one.

I am no sure there is a wiring diagram as such available for Fortwo's other than way is available via the MB Star DAS / WIS system. You will need to trace the wiring from the bulb back to the loom and see if you are getting any voltage there. Then trace the wiring from there to the next joint and check there. Carry on doing this until you find the culprit.

I would hazard a guess that it is a broken wire or joint rather than a specific unit as the ABS system is generally quite robust. There have been a few issues with the ABS pump, but I can't see that producing your error and not being logged.

John

[Mad smart person]

Re: ABS light not on / ESP logged ! fault

Greetings John, I like your sense of humour? Tracing the wiring, that's like trying to find a ferret that's run up a chaps leg - something you'd not enjoy!!
There is a fault logged but it's a (!) not a F or f. So what does an ! mean?? I was hoping someone had a wiring diagram with at least wire colours and boxes they went to. That way, I'd at least be able to check the continuity of the wires. I'm of the opinion something supplies the 12 volts to turn the light on and something else, once the test of the circuits has passed, either removes the 12 volts, or the earth that allows the light to glow.
Cheers, Ian.

[madDan]

Re: ABS light not on / ESP logged ! fault

Did you have diags run on inst cluster as well?

[137699]

Re: ABS light not on / ESP logged ! fault

I would try another cluster. Maybe a previous owner cut a track on the PCB to prevent the bulb from lighting? Because they knew pulling out the bulb would be too easily found out?

[tolsen]

Re: ABS light not on / ESP logged ! fault

ABS warning light signal to instrument panel goes via CAN network. Then no point looking for cable faults outside the instrument cluster unless you have CAN faults.

[Mad smart person]

Re: ABS light not on / ESP logged ! fault

Greetings all, I've not had a diagnostics run on th e inst. cluster, will get that tried, although it did come up with a 'tick', when the diagnostics were run first and when the ESP came up with a '!', which has me intrigued. I've just had the inst cluster out and dismantled it as much as I could without taking the pointer off and there's no sign of any track cuts, corrosion or other damage. I think I may have been the first person to pull it to bits unless it was done before very carefully the first time? As I had the passenger seat out anyway, I tried the yaw sensor - just on the off chance - no change there. Next is going to be either the SAM out or the electronic buggery box on the back of the ABS unit, it'll all depend on the toss of coin. After that I'm shagged. Any other idea's????? Cheers.

[Mad smart person]

Re: ABS light not on / ESP logged ! fault

Greetings All, the saga continues. Should have taken some of the advice above about the instrument cluster. But just because I like self punishment I took out the SAM and pulled it to bits. At least I can say the SAM looks to be in fine fettle, no corrosion, green stuff or dry solder joints. Put it back in and, you guessed it, no change. Grabbed an inst. cluster I have from a 600 fortwo, plugged it in and, to the members above, you guys were on the nail, ABS light works as it should. But just as you know, the odometer reads the mileage of the car it came from. So, a few new questions, will a 600 cluster work in a 700, once it's been reprogrammed?? Can it be reprogrammed? If so, can a clone star machine do it or does one have to get the local friendly Merc. dealer to do it? If it can be done by a 'clone' star, how does one go about that? Or does one have to buy a 700 cluster and carry on from there?? Cheers, Ian.

[tolsen]

Re: ABS light not on / ESP logged ! fault

I suggest you open out instrument cluster another time and check out the tracks to your ABS light. Probably best measuring the tracks for continuity using a multimeter.

[Mad smart person]

Re: ABS light not on / ESP logged ! fault

Greetings, thanks, I'll do that again. What troubles me is, there are a lot of little things in there that look like mutant spiders, not 8 legs but many more legs. And, if it's all controlled by the CAN bus, it'll be one or more of those little spiders that would be the cause??? Will let you know of progress? Cheers, Ian.

[Mad smart person]

Re: ABS light not on / ESP logged ! fault

Greetings All, the saga has been sorted. A man with a very special microscope, one that can see where the '0's and '1's are leaking out, found that for some reason the coding had become corrupted. He's corrected the 0 & 1 stream and now the ABS light works as it should. He suggested the probable cause of the data corruption was a voltage 'spike'. Those Germans definitely "didn't like that cold steel up em, did they"?? They've found a way to get back........... All's well that ends well.
Cheers, Ian.