Experts to find/fix electrical problems?

ItalianTuneUp

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My car has a number of annoying messages that sometimes appear on the dash and before playing the 'could be this, or could be that expensive game', I thought I'd see if there are any garages or engineers that people here could recommend.

Messages I've seen include:
. Electronic power control (see this every day)
. Auto lights switch setting fails to light headlamps when it is dark, but this might be fixed now as new bulb fitted, need to check
. Battery charge in red (predictable, happens often when lifting off gas and letting car slow naturally)
. Occasional weird freaky events where the Speedo/rev needles swing around wildly and all lights on the dash do their Christmas lights impression, followed by car slowing down, jolting, loss of power. Fixed by turning ignition off and on again!
. Occasional ignition failure, turn key to ignition position but nothing happens, just silence. It always starts eventually, but is random and there is no way of predicting how long it will be before successful ignition...no good for my bank getaways! I might need to start throwing salt over my shoulder soon for good luck, ha ha!
. some other infrequent ones, which I've forgotten

Any tips, advice or recommendations welcomed.

I would like to find an expert in MB electrics who is going to find & fix these gremlins without drama and at a reasonable cost, if this is possible.
 
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ItalianTuneUp

ItalianTuneUp

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Yep, was thinking of doing so when the next service is due, which is quite soon. Thanks.
 
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I tested the auto lights switch position and all seems well again, so that problem seems to have gone away.
 

alfhoc

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My car has a number of annoying messages that sometimes appear on the dash and before playing the 'could be this, or could be that expensive game', I thought I'd see if there are any garages or engineers that people here could recommend.

Messages I've seen include:
. Electronic power control (see this every day)
. Auto lights switch setting fails to light headlamps when it is dark, but this might be fixed now as new bulb fitted, need to check
. Battery charge in red (predictable, happens often when lifting off gas and letting car slow naturally)
. Occasional weird freaky events where the Speedo/rev needles swing around wildly and all lights on the dash do their Christmas lights impression, followed by car slowing down, jolting, loss of power. Fixed by turning ignition off and on again!
. Occasional ignition failure, turn key to ignition position but nothing happens, just silence. It always starts eventually, but is random and there is no way of predicting how long it will be before successful ignition...no good for my bank getaways! I might need to start throwing salt over my shoulder soon for good luck, ha ha!
. some other infrequent ones, which I've forgotten

Any tips, advice or recommendations welcomed.

I would like to find an expert in MB electrics who is going to find & fix these gremlins without drama and at a reasonable cost, if this is possible.

Looking ar all you have decsribed it sounds as if you have a bad ground connection somewhere.
 
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ItalianTuneUp

ItalianTuneUp

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Looking ar all you have decsribed it sounds as if you have a bad ground connection somewhere.

Thanks for that, I will need to check that out! Just out of interest, what makes you think that? I'm not doubting you, I would just like to understand more. Thanks a lot.
 

stevehg

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Multiple faults at once and things like gauge issues are common symptoms of voltage issues. So could be battery on its way out or grounding issues as stated above. Couple it with this time of the year and this symptom of battery light coming on when you lift off and at low revs and I'd say it was most likely to be a battery issue. Have you checked the voltage of the battery?

If it is its a quick, easy and relatively cheap fix.

Cheers

Steve
 

dozypillock

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How does one go about finding a bad ground connection?

Normally just a case of looking for a group of black wires bolted to the body somewhere, especially in areas where surface rust looks to be present.

Neil
 
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ItalianTuneUp

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Multiple faults at once and things like gauge issues are common symptoms of voltage issues. So could be battery on its way out or grounding issues as stated above. Couple it with this time of the year and this symptom of battery light coming on when you lift off and at low revs and I'd say it was most likely to be a battery issue. Have you checked the voltage of the battery?

If it is its a quick, easy and relatively cheap fix.

Cheers

Steve

The battery is less than a year old and it is a top notch battery: silver Varta.

However, aren't there 2 batteries in some MBs?

So it could be down to a grounding issue perhaps? Lifting off the gas and seeing the red battery charge message is quite reproducible, can be made to happen on demand quite easily.

I'm also wondering what the Electronic Power Control message is all about...hopefully not something that will cost lots to fix!
 
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Multiple faults at once and things like gauge issues are common symptoms of voltage issues. So could be battery on its way out or grounding issues as stated above. Couple it with this time of the year and this symptom of battery light coming on when you lift off and at low revs and I'd say it was most likely to be a battery issue. Have you checked the voltage of the battery?

If it is its a quick, easy and relatively cheap fix.

Cheers

Steve

The red battery charge message has been happening most of the year, even summer, so I don't think it's exacerbated by rain.

I'm thinking it could be alternator related perhaps? Hopefully not, but could be? The thing is that there is never any battery power issue starting the ignition...always starts without issue. The only exception to this is when the issue mentioned above occurs, and then the car is silent when ignition attempted, but that is a very rare issue, luckily.
 
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ItalianTuneUp

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Just had an idea after remembering a 'put your hand up to a stupid moment' tale where a scrapyard component rolled across footwell and jammed the brake pedal...could it be that as I lift off the gas, the car shifts position slightly, fore or aft dive, which then causes a loose electrical connection to move, thus breaking contact?
 
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Driving through the wind & rain yesterday, I had the dash lights all light up, the speedo/rev needles swung around wildly, a jolt in power delivery etc, and I thought 'here we go again'.

There was also a message saying something like 'Pre-safe not available!'.

Luckily there was a lay by, so I pulled in and turned the ignition off and on again...like the IT Crowd advice, and all was well again. It's happened very occasionally, maybe 5 times or so in the last year, perhaps occurring mostly when driving in windy & rainy weather, but not exclusively.

Has anyone else experienced something similar?

Interestingly, when I stopped the car at some later point in the journey, there was only one malfunction message about battery charge in red, but there was no 'Electronic Power Control' message, which normally seems to occur on every journey.
 
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John

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Ok thanks. I think it's galvanized.

You still get surface corrosion. My car is galvanised but I've had to deal with inside rear wheel arch rust.

The only way to be sure would be to remove, clean up all the terminals with wire wool as well as the surface they make contact with and try again - if you've ever seen a car with the indicators going and most of the other lights are dim and flashing the same - that's a poor ground. I imagine in these cars - it plays havoc!

Also, I had read on here that Varta batteries weren't as good as the Merc ones although I have no idea who makes Merc batteries (Bosch?).

Even after all that - I've yet to solve my quirks. I presume it is still damp and / or cold that affects.

My situation is different at the moment though because I changed my wheels and when I replaced the fronts, I replaced like for like so I am running CLS size fronts until they wear out. So I've been regularly getting the ride height issue but it's not worth changing the fronts to fix it albeit it still happens but just periodically with the right size tyres.
 
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Been out in the beast today and, again, there was no mention of the 'electronic power control' message. Maybe it's got bored of repeating itself...wishful thinking perhaps but that's twice I haven't seen this message, when I used to see it every trip. Maybe getting both the low beam headlamp bulbs replaced has done the trick? I doubt it but I'll wait and see.
 
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V12

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EPC message could be triggered by inlet and /or fuel issues. Low fuel pressure for example or EGR issues. This should be easy to find on star.

Auto headlight sensitivity can be adjusted in star if it's currently not sensitive enough.

I wouldn't worry about ground issues in the normal places in your car, it's much too clean for that. IIRC it has had some rear end bodywork? I wonder if any of the wires in the rear loom have been crimped by the bodywork or disturbed and maybe a funny short.

The Varta silver battery is definitely man enough for the job. Varta manufacture batteries for Bosch, MB, BMW, Porsche and plenty of other OEM applications.
I have had mine longer than you and my car has no low voltage issues. I mostly do short trips. Maybe you do have a weak alternator though?
 
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Well it gets weirder...since replacing the second headlamp low beam bulb there have not been any EPC messages displayed.

The bad news is that I have seen multiple occasions of the dash lights all lighting up and flashing simultaneously, jolt in power delivery...was out and about a lot in the wind and rain last couple of days doing house maintenance stuff and this has happened quite a few times. The temporary fix is easy...simply turn off and on again, but I don't like the sudden jolt in power delivery...it feels a little brutal and is a right PITA.

I'm really beginning to suspect that somehow moisture is getting into electrics and making them go haywire. There's no smell of damp in the car, so I'm beginning to wonder if moisture is getting into external fuses or something like that. I suppose the mighty STAR is next.

Thinking about the bulb being changed and not seeing any more EPC messages, when there's been a lot of rain, I've seen the headlamps fog slightly inside, so maybe the EPC messages and/or the problems just described are related to moisture on external-to-the-cabin electrical contacts, like bulb contacts for example. A temporary fix might be to get the hairdryer on some electrics to blast the moisture out? The tentative link with rain and wind seems to be getting stronger.
 
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dozypillock

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Well it gets weirder...since replacing the second headlamp low beam bulb there have not been any EPC messages displayed.

The bad news is that I have seen multiple occasions of the dash lights all lighting up and flashing simultaneously, jolt in power delivery...was out and about a lot in the wind and rain last couple of days doing house maintenance stuff and this has happened quite a few times. The temporary fix is easy...simply turn off and on again, but I don't like the sudden jolt in power delivery...it feels a little brutal and is a right PITA.

I'm really beginning to suspect that somehow moisture is getting into electrics and making them go haywire. There's no smell of damp in the car, so I'm beginning to wonder if moisture is getting into external fuses or something like that. I suppose the mighty STAR is next.

Thinking about the bulb being changed and not seeing any more EPC messages, when there's been a lot of rain, I've seen the headlamps fog slightly inside, so maybe the EPC messages and/or the problems just described are related to moisture on external-to-the-cabin electrical contacts, like bulb contacts for example. A temporary fix might be to get the hairdryer on some electrics to blast the moisture out? The tentative link with rain and wind seems to be getting stronger.

I assume you have checked the main battery terminals are clean, and tight, especially after having a new battery fitted last year.
Complete power failure can be caused by things like that. In summer alternator does not do much, but in rain etc, probably got lights on, wipers on, heated windows etc, so not enough power from alternator on its own to run everything, if battery has disconnected. Would also explain low charge light.
Probably worth getting sorted sooner, rather than later as running without battery, even for short periods can damage other bits.
Just a thought.

Neil
 

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